TDS 420A, TDS 430A & TDS 460A Digitizing Oscilloscopes 070

Service Manual

TDS 420A, TDS 430A & TDS 460ADigitizing Oscilloscopes

070-9703-04

This document applies to instruments with serialnumbers B050000 and above.

WarningThe servicing instructions are for use by qualifiedpersonnel only. To avoid personal injury, do notperform any servicing unless you are qualified todo so. Refer to the Safety Summary prior toperforming service.

Copyright � Tektronix, Inc. All rights reserved.

Tektronix products are covered by U.S. and foreign patents, issued and pending. Information in this publication supercedesthat in all previously published material. Specifications and price change privileges reserved.

Printed in the U.S.A.

Tektronix, Inc., P.O. Box 1000, Wilsonville, OR 97070–1000

TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.

KlipChip is a trademark of Tektronix, Inc.

WARRANTY

Tektronix warrants that the products that it manufactures and sells will be free from defects in materials and workmanshipfor a period of three (3) years from the date of shipment. If a product proves defective during this warranty period,Tektronix, at its option, either will repair the defective product without charge for parts and labor, or will provide areplacement in exchange for the defective product.

In order to obtain service under this warranty, Customer must notify Tektronix of the defect before the expiration of thewarranty period and make suitable arrangements for the performance of service. Customer shall be responsible forpackaging and shipping the defective product to the service center designated by Tektronix, with shipping charges prepaid.Tektronix shall pay for the return of the product to Customer if the shipment is to a location within the country in which theTektronix service center is located. Customer shall be responsible for paying all shipping charges, duties, taxes, and anyother charges for products returned to any other locations.

This warranty shall not apply to any defect, failure or damage caused by improper use or improper or inadequatemaintenance and care. Tektronix shall not be obligated to furnish service under this warranty a) to repair damage resultingfrom attempts by personnel other than Tektronix representatives to install, repair or service the product; b) to repairdamage resulting from improper use or connection to incompatible equipment; c) to repair any damage or malfunctioncaused by the use of non-Tektronix supplies; or d) to service a product that has been modified or integrated with otherproducts when the effect of such modification or integration increases the time or difficulty of servicing the product.

THIS WARRANTY IS GIVEN BY TEKTRONIX IN LIEU OF ANY OTHER WARRANTIES, EXPRESS ORIMPLIED. TEKTRONIX AND ITS VENDORS DISCLAIM ANY IMPLIED WARRANTIES OFMERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. TEKTRONIX’ RESPONSIBILITY TOREPAIR OR REPLACE DEFECTIVE PRODUCTS IS THE SOLE AND EXCLUSIVE REMEDY PROVIDED TOTHE CUSTOMER FOR BREACH OF THIS WARRANTY. TEKTRONIX AND ITS VENDORS WILL NOT BELIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES IRRESPECTIVEOF WHETHER TEKTRONIX OR THE VENDOR HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCHDAMAGES .

TDS 420A, TDS 430A & TDS 460A Service Manual i

Table of Contents

List of Figures iii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

List of Tables vi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . General Safety Summary ix. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Service Safety Summary xi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Preface xiii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Introduction xvi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Before Servicing xvi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Strategy for Servicing xvi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tektronix Service xvii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SpecificationsProduct Description 1–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nominal Traits 1–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Warranted Characteristics 1–15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Typical Characteristics 1–21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Operating InformationInstallation 2–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Supplying Operating Power 2–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Operating Environment 2–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Applying and Interrupting Power 2–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Repackaging Instructions 2–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Installed Options 2–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Operating Information 2–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Screen Layout 2–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Basic Procedures 2–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Theory of OperationTheory of Operation 3–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Logic Conventions 3–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Module Overview 3–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Performance VerificationPerformance Verification Procedures 4–1. . . . . . . . . . . . . . . . . . . . . . . . . .

Brief Procedures 4–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Self Tests 4–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Functional Tests 4–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Performance Tests 4–15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Prerequisites 4–15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Equipment Required 4–16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Test Record 4–18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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ii TDS 420A, TDS 430A & TDS 460A Service Manual

Signal Acquisition System Checks 4–20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Time Base System Checks 4–34. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Trigger System Checks 4–38. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Output Signal Check 4–53. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sine Wave Generator Leveling Procedure 4–55. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Adjustment ProceduresAdjustment Procedures 5–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Requirements for Performance 5–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Usage 5–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Equipment Required 5–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Adjustment Instructions 5–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Probe Adjustment 5–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Monitor Assembly Adjustment 5–21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

MaintenanceMaintenance 6–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Related Maintenance Procedures 6–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Preparation 6–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Inspection and Cleaning 6–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Removal and Installation Procedures 6–9. . . . . . . . . . . . . . . . . . . . . . . . . . Preparation — Please Read 6–9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Access Procedure 6–13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Procedures for Module Removal and Installation 6–23. . . . . . . . . . . . . . . . . . . . . . . . Disassembly for Cleaning 6–65. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Troubleshooting 6–69. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Diagnostics 6–69. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Firmware Updates 6–70. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Troubleshooting Equipment 6–71. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

OptionsElectrical Parts ListDiagramsMechanical Parts List

Table of Contents

TDS 420A, TDS 430A & TDS 460A Service Manual iii

List of Figures

Figure 1–1: TDS 400A Dimensional Drawing 1–13. . . . . . . . . . . . . . . . . . . .

Figure 2–1: Map of Display Functions 2–8. . . . . . . . . . . . . . . . . . . . . . . . .

Figure 4–1: Map of Display Functions 4–3. . . . . . . . . . . . . . . . . . . . . . . . .

Figure 4–2: Verifying Adjustments and Signal Path Compensation 4–6. Figure 4–3: Universal Test Hookup for Functional Tests 4–8. . . . . . . . . .

Figure 4–4: Initial Test Hookup 4–20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 4–5: Initial Test Hookup 4–23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 4–6: Initial Test Hookup 4–26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 4–7: Measurement of Analog Bandwidth 4–29. . . . . . . . . . . . . . . . . Figure 4–8: Initial Test Hookup 4–31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 4–9: Measurement of Channel Delay 4–33. . . . . . . . . . . . . . . . . . . . Figure 4–10: Initial Test Hookup 4–34. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 4–11: Measurement of Accuracy — Long-Term and Delay-Time 4–37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 4–12: Initial Test Hookup 4–38. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 4–13: Initial Test Hookup 4–41. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 4–14: Measurement of Trigger Sensitivity 4–43. . . . . . . . . . . . . . . .

Figure 4–15: Initial Test Hookup 4–45. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 4–16: Confirming Auxiliary Triggering at Maximum

Triggering Frequency 4–46. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 4–17: Initial Test Hookup 4–47. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 4–18: Adjusting Sync Pulse Amplitude 4–49. . . . . . . . . . . . . . . . . . .

Figure 4–19: Measurement of Video Sensitivity 4–50. . . . . . . . . . . . . . . . . . Figure 4–20: Initial Test Hookup 4–52. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 4–21: Initial Test Hookup 4–54. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 4–22: Measurement of Probe Compensator Limits 4–55. . . . . . . . .

Figure 4–23: Sine Wave Generator Leveling Equipment Setup 4–56. . . . . Figure 4–24: Equipment Setup for maximum Amplitude 4–57. . . . . . . . . .

Figure 5–1: Hookup for Probe Compensation 5–10. . . . . . . . . . . . . . . . . . . Figure 5–2: Performing Probe Compensation 5–11. . . . . . . . . . . . . . . . . . .

Figure 5–3: Proper and Improper Probe Compensation 5–12. . . . . . . . . . . Figure 5–4: Exposing the Inner Probe Tip 5–13. . . . . . . . . . . . . . . . . . . . . .

Figure 5–5: Initial Test Hookup 5–13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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iv TDS 420A, TDS 430A & TDS 460A Service Manual

Figure 5–6: Exposing the Probe Body 5–16. . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 5–7: Initial Test Hookup 5–16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 5–8: Probe Test Hookup 5–18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 5–9: Locations of Probe Adjustments 5–19. . . . . . . . . . . . . . . . . . . . Figure 5–10: Adjustments vs. Front-Corner Response 5–20. . . . . . . . . . . .

Figure 5–11: Monitor Adjustment Locations 5–23. . . . . . . . . . . . . . . . . . . .

Figure 5–12: Five and Ten Percent Luminance Patches 5–24. . . . . . . . . . . Figure 5–13: Composite Pattern for Focusing 5–25. . . . . . . . . . . . . . . . . . .

Figure 6–1: Oscilloscope Orientation 6–11. . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6–2: Cabinet and Front-Panel Mounted Modules 6–16. . . . . . . . . . Figure 6–3: Internal Modules 6–19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6–4: Cables and Cable Routing 6–22. . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6–5: Knob and Shaft Removal 6–24. . . . . . . . . . . . . . . . . . . . . . . . . . Figure 6–6: Line Fuse and Line Cord Removal 6–25. . . . . . . . . . . . . . . . . .

Figure 6–7: Front Cover, Rear Cover, Cabinet, EMI Gasket, and Cabinet Handle and Feet Removal 6–27. . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6–8: Trim Ring, Menu Elastomer, and Menu Buttons Removal 6–30. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6–9: EMI Gasket Removal and Installation 6–32. . . . . . . . . . . . . . . Figure 6–10: Disk Drive Removal 6–33. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6–11: A06 Front-Panel Assembly, ESD Shield, and Menu Flex and Probe Code Flex Circuits Removal 6–35. . . . . . . . . . . . . . . . .

Figure 6–12: Disassembly of the Front-Panel Assembly 6–36. . . . . . . . . . .

Figure 6–13: A05 Attenuator Removal 6–39. . . . . . . . . . . . . . . . . . . . . . . . . Figure 6–14: A26 Monitor Assembly Removal 6–42. . . . . . . . . . . . . . . . . . .

Figure 6–15: A08 Jumper Board Assembly, D1 Bus, and Board Supports Removal 6–43. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6–16: A03 CPU Removal 6–45. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6–17: A02 Display Assembly Removal 6–47. . . . . . . . . . . . . . . . . . . Figure 6–18: A09 DSP Assembly Removal 6–48. . . . . . . . . . . . . . . . . . . . . .

Figure 6–19: A01 Backplane Assembly and its Mount Removal 6–50. . . . Figure 6–20: Battery Removal 6–53. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6–21: A25 Low Voltage Power Supply Removal 6–55. . . . . . . . . . . Figure 6–22: Fan and Fan Mount Removal 6–58. . . . . . . . . . . . . . . . . . . . .

Figure 6–23: Line Filter Removal 6–59. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6–24: Auxiliary Power Supply Removal 6–62. . . . . . . . . . . . . . . . . . Figure 6–25: A04 Acquisition Board Removal 6–64. . . . . . . . . . . . . . . . . . .

Figure 6–26: Accessing the Protection Switch 6–70. . . . . . . . . . . . . . . . . . .

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TDS 420A, TDS 430A & TDS 460A Service Manual v

Figure 6–27: Console Port Connections 6–73. . . . . . . . . . . . . . . . . . . . . . . .

Figure 6–28: Primary Troubleshooting Procedure 6–74. . . . . . . . . . . . . . . Figure 6–29: A03 CPU Board Connector P1 6–75. . . . . . . . . . . . . . . . . . . .

Figure 6–30: Module Isolation Troubleshooting Procedure 6–76. . . . . . . . Figure 6–31: Low Voltage Power Supply Troubleshooting Procedure 6–78

Figure 6–32: Power Supply Overload Troubleshooting Procedure 6–80. .

Figure 6–33: A25 Low Voltage Power Supply Module (Right Side) 6–81. . Figure 6–34: Monitor Troubleshooting Procedure 6–82. . . . . . . . . . . . . . . .

Figure 6–35: Horizontal and Vertical Sync Signals 6–83. . . . . . . . . . . . . . . Figure 6–36: A Video Signal with White, Black, and Blanking Levels 6–83

Figure 6–37: A26 Monitor Connector J440 6–84. . . . . . . . . . . . . . . . . . . . . . Figure 6–38: A07 Auxiliary Power Connectors J4 and J7 6–84. . . . . . . . . .

Figure 6–39: A02 Display Connector J2 6–85. . . . . . . . . . . . . . . . . . . . . . . . Figure 6–40: Processor/Front Panel Troubleshooting Procedure 6–86. . . .

Figure 6–41: A06 Front Panel Board Power Connectors J101 and J106 6–87. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6–42: Attenuator/Acquisition Troubleshooting Procedure 6–88. . .

Figure 6–43: A08 Jumper and A05 Attenuator Boards Signal Locations 6–89. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6–44: Acquisition and Attenuator Power Troubleshooting Procedure 6–90. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6–45: A04 Acquisition Board Power Connector 6–91. . . . . . . . . . . .

Figure 6–46: Backplane Troubleshooting Procedure 6–92. . . . . . . . . . . . . . Figure 6–47: A01 Backplane Module 6–94. . . . . . . . . . . . . . . . . . . . . . . . . . .

Figure 6–48: I2C Isolation Troubleshooting Procedure 6–95. . . . . . . . . . . . Figure 6–49: Console Troubleshooting Procedure 6–96. . . . . . . . . . . . . . . .

Figure 9–1: TDS 400A Interconnections 9–2. . . . . . . . . . . . . . . . . . . . . . . .

Figure 9–1: TDS 400A Interconnections (Cont.) 9–3. . . . . . . . . . . . . . . . .

Figure 9–2: TDS 400A Block Diagram 9–4. . . . . . . . . . . . . . . . . . . . . . . . . Figure 9–2: TDS 400A Block Diagram (Cont.) 9–5. . . . . . . . . . . . . . . . . . .

Figure 10–1: External and Front Panel Modules 10–7. . . . . . . . . . . . . . . . .

Figure 10–2: Internal Modules 10–9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Figure 10–3: Cables and Routing 10–11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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vi TDS 420A, TDS 430A & TDS 460A Service Manual

List of Tables

Table 1–1: Key Features of the TDS 400A Oscilloscopes 1–1. . . . . . . . . .

Table 1–2: Record Length vs. Divisions per Record 1–3. . . . . . . . . . . . . . Table 1–3: Nominal Traits — Signal Acquisition System 1–7. . . . . . . . . .

Table 1–4: Nominal Traits — Time Base System 1–9. . . . . . . . . . . . . . . . Table 1–5: Nominal Traits — Triggering System 1–9. . . . . . . . . . . . . . . .

Table 1–6: Nominal Traits — Display System 1–10. . . . . . . . . . . . . . . . . . . Table 1–7: Nominal Traits — Data Storage 1–10. . . . . . . . . . . . . . . . . . . . .

Table 1–8: Nominal Traits — GPIB Interface, Video Output, and Power Fuse 1–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1–9: Nominal Traits — Mechanical 1–11. . . . . . . . . . . . . . . . . . . . . .

Table 1–10: Warranted Characteristics — Signal Acquisition System 1–15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1–11: Warranted Characteristics — Time Base System 1–17. . . . . . Table 1–12: Warranted Characteristics — Triggering System 1–18. . . . .

Table 1–13: Warranted Characteristics — Probe Compensator Output 1–18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1–14: Warranted Characteristics — Power Requirements 1–18. . .

Table 1–15: Warranted Characteristics — Environmental, Safety, and Reliability 1–19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1–16: Certifications and compliances 1–20. . . . . . . . . . . . . . . . . . . . . Table 1–17: Typical Characteristics — Signal Acquisition System 1–21. .

Table 1–18: Typical Characteristics — Time Base System 1–22. . . . . . . . . Table 1–19: Typical Characteristics — Triggering System 1–23. . . . . . . .

Table 1–20: Typical Characteristics — Data Handling 1–24. . . . . . . . . . .

Table 2–1: Power-Cord Conductor Identification 2–2. . . . . . . . . . . . . . . .

Table 2–2: Power Cord Identification 2–2. . . . . . . . . . . . . . . . . . . . . . . . . Table 2–3: Effects of Corrupted Data 2–4. . . . . . . . . . . . . . . . . . . . . . . . . .

Table 4–1: Test Equipment 4–16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 4–2: DC Offset Accuracy 4–22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 4–3: Analog Bandwidth (TDS 420A) 4–27. . . . . . . . . . . . . . . . . . . . . Table 4–4: Analog Bandwidth (TDS 430A and TDS 460A) 4–28. . . . . . . .

Table 5–1: Adjustments Required for Module Replaced 5–3. . . . . . . . . .

Table 5–2: Adjustments and Dependencies 5–4. . . . . . . . . . . . . . . . . . . . . Table 5–3: Test Equipment, Fixtures, and Supplies 5–5. . . . . . . . . . . . . .

Table of Contents

TDS 420A, TDS 430A & TDS 460A Service Manual vii

Table 5–4: GPIB Board Configuration1 5–7. . . . . . . . . . . . . . . . . . . . . . . .

Table 6–1: Relative Susceptibility to Static-Discharge Damage 6–3. . . . .

Table 6–2: External Inspection Check List 6–5. . . . . . . . . . . . . . . . . . . . . Table 6–3: Internal Inspection Check List 6–6. . . . . . . . . . . . . . . . . . . . . .

Table 6–4: Tools Required for Module Removal 6–12. . . . . . . . . . . . . . . . .

Table 6–5: Access Instructions for Modules in Figure 6–2 6–15. . . . . . . . . Table 6–6: Access Instructions for Modules in Figure 6–3 6–17. . . . . . . . .

Table 6–7: Access (and Removal) Instructions for Cables in Figure 6–4 6–20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 6–8: Troubleshooting Test Equipment, Fixtures, and Supplies 6–71. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 6–9: Connections for a 9 to 25 Pin Null Modem Cable 6–72. . . . . .

Table 6–10: Diagnostic Failure Priority Lists 6–77. . . . . . . . . . . . . . . . . . . Table 6–11: Normal Output Voltage 6–79. . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 6–12: Power Supply Maximum Current 6–81. . . . . . . . . . . . . . . . . . Table 6–13: Front Panel Connector Voltages 6–87. . . . . . . . . . . . . . . . . . . .

Table 6–14: Channel and P1 Signal Locations 6–89. . . . . . . . . . . . . . . . . . . Table 6–15: A05 Attenuator Board Power 6–90. . . . . . . . . . . . . . . . . . . . . .

Table 6–16: A04 Acquisition Board Power 6–91. . . . . . . . . . . . . . . . . . . . . . Table 6–17: Regulator Voltages 6–93. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 6–18: J7 Voltages 6–93. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 6–19: J8 Front Panel Voltages 6–93. . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 7–1: International Power Cords 7–2. . . . . . . . . . . . . . . . . . . . . . . . . Table 7–2: Standard Accessories 7–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 7–3: Optional Accessories 7–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Table 7–4: Compatible Probes 7–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 7–5: Accessory Software 7–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table of Contents

viii TDS 420A, TDS 430A & TDS 460A Service Manual

TDS 420A, TDS 430A & TDS 460A Service Manual ix

General Safety Summary

Review the following safety precautions to avoid injury and prevent damage tothis product or any products connected to it.

To avoid potential hazards, use this product only as specified.

Only qualified personnel should perform service procedures.

Use Proper Power Cord. To avoid fire hazard, use only the power cord specifiedfor this product.

Avoid Electric Overload. To avoid electric shock or fire hazard, do not apply avoltage to a terminal that is outside the range specified for that terminal.

Avoid Electric Shock. To avoid injury or loss of life, do not connect or disconnectprobes or test leads while they are connected to a voltage source.

Ground the Product. This product is grounded through the grounding conductorof the power cord. To avoid electric shock, the grounding conductor must beconnected to earth ground. Before making connections to the input or outputterminals of the product, ensure that the product is properly grounded.

Do Not Operate Without Covers. To avoid electric shock or fire hazard, do notoperate this product with covers or panels removed.

Use Proper Fuse. To avoid fire hazard, use only the fuse type and rating specifiedfor this product.

Do Not Operate in Wet/Damp Conditions. To avoid electric shock, do not operatethis product in wet or damp conditions.

Do Not Operate in an Explosive Atmosphere. To avoid injury or fire hazard, do notoperate this product in an explosive atmosphere.

Use Proper Power Source. Do not operate this product from a power source thatapplies more than the voltage specified.

Provide Proper Ventilation. To prevent product overheating, provide properventilation.

Do Not Operate With Suspected Failures. If you suspect there is damage to thisproduct, have it inspected by qualified service personnel.

Injury Precautions

Product DamagePrecautions

General Safety Summary

x TDS 420A, TDS 430A & TDS 460A Service Manual

Terms in this Manual. These terms may appear in this manual:

WARNING. Warning statements identify conditions or practices that could resultin injury or loss of life.

CAUTION. Caution statements identify conditions or practices that could result indamage to this product or other property.

Terms on the Product. These terms may appear on the product:

DANGER indicates an injury hazard immediately accessible as you read themarking.

WARNING indicates an injury hazard not immediately accessible as you read themarking.

CAUTION indicates a hazard to property including the product.

Symbols on the Product. The following symbols may appear on the product:

Protective Ground(Earth) Terminal

ATTENTIONRefer to Manual

Double Insulated

DANGERHigh Voltage

Refer to the specifications section for a listing of certifications and compliancesthat apply to this product.

Symbols and Terms

Certifications andCompliances

TDS 420A, TDS 430A & TDS 460A Service Manual xi

Service Safety Summary

Only qualified personnel should perform service procedures. Read this ServiceSafety Summary and the General Safety Summary before performing any serviceprocedures.

Do Not Service Alone. Do not perform internal service or adjustments of thisproduct unless another person capable of rendering first aid and resuscitation ispresent.

Disconnect Power. To avoid electric shock, disconnect the main power by meansof the power cord or, if provided, the power switch.

Use Caution When Servicing the CRT. To avoid electric shock or injury, useextreme caution when handling the CRT. Only qualified personnel familiar withCRT servicing procedures and precautions should remove or install the CRT.

CRTs retain hazardous voltages for long periods of time after power is turned off.Before attempting any servicing, discharge the CRT by shorting the anode tochassis ground. When discharging the CRT, connect the discharge path to groundand then the anode. Rough handling may cause the CRT to implode. Do not nickor scratch the glass or subject it to undue pressure when removing or installing it.When handling the CRT, wear safety goggles and heavy gloves for protection.

Use Care When Servicing With Power On. Dangerous voltages or currents mayexist in this product. Disconnect power, remove battery (if applicable), anddisconnect test leads before removing protective panels, soldering, or replacingcomponents.

To avoid electric shock, do not touch exposed connections.

X-Radiation. To avoid x-radiation exposure, do not modify or otherwise alter thehigh-voltage circuitry or the CRT enclosure. X-ray emissions generated withinthis product have been sufficiently shielded.

Service Safety Summary

xii TDS 420A, TDS 430A & TDS 460A Service Manual

TDS 420A, TDS 430A & TDS 460A Service Manual xiii

Preface

This service manual provides service information for the TDS 420A, TDS 430A,and TDS 460A Digitizing Oscilloscopes.

STOP. If servicing a TDS 430A, follow the procedures for the TDS 460A, butignore all references to CH 3 and CH 4.

Manual StructureThis manual is divided into Chapters such as Specifications and Theory ofOperation. Further, it is divided into subsections such as Product Descriptionand Removal and Installation Procedures.

Sections containing procedures also contain introductions to those procedures.Be sure to read these introductions because they provide information needed todo the service correctly and efficiently. A brief description of each manualchapter follows:

� Specifications contains a product description of the digitizing oscilloscopeand tables of the characteristics and descriptions that apply to it.

� Operating Information is this chapter. It includes a description of how thismanual is structured as well as general information and operating instruc-tions at the level needed to safely power on and service this oscilloscope. Astatement of the service strategy that this manual supports and instructionsfor shipment of the digitizing oscilloscope are found in this chapter.

� Theory of Operation contains circuit descriptions that support general serviceand fault isolation.

� Performance Verification contains a collection of procedures for confirmingthat this digitizing oscilloscope functions properly and meets warrantedlimits.

� Adjustment Procedures contains a collection of procedures for adjusting thisdigitizing oscilloscope to meet warranted limits.

� Maintenance contains information and procedures for doing preventive andcorrective maintenance of the digitizing oscilloscope. Instructions forcleaning, for module removal and installation, and for fault isolation to amodule are found here.

Preface

xiv TDS 420A, TDS 430A & TDS 460A Service Manual

� Options contains information on the factory-installed options that may bepresent in your oscilloscope.

� Electrical Parts List contains a statement referring you to the MechanicalParts List, where both electrical and mechanical modules are listed. See below.

� Diagrams contains a block diagram and an interconnection diagram usefulfor isolating failed modules.

� Mechanical Parts List includes a table of all replaceable modules, theirdescriptions, and their Tektronix part numbers.

Manual ConventionsThis manual uses certain conventions which you should become familiar withbefore doing service.

Throughout this manual, any replaceable component, assembly, or part of thisdigitizing oscilloscope is referred to generically as a module. In general, amodule is an assembly, like a circuit board, rather than a component, like aresistor or an integrated circuit. Sometimes a single component is a module; forexample, the chassis of the oscilloscope is a module.

Symbols and terms related to safety appear in the General Safety Summary andService Safety Summary found at the beginning of this manual.

Besides the symbols related to safety, this manual uses the following symbols:

STOP. This “stop sign” labels information which you must read in order tocorrectly do service and to avoid incorrectly using or applying service procedures.

The clock icon labels procedure steps which require a pause to waitfor the oscilloscope to complete some operation before you can continue.

Various icons such as the example icon at the left are used inprocedures to help identify certain readouts and menu functions on screen.

Modules

Safety

Symbols

Preface

TDS 420A, TDS 430A & TDS 460A Service Manual xv

Related ManualsThese other manuals are available for the TDS 430A, TDS 420A, and TDS 460ADigitizing Oscilloscopes:

� The Reference gives you a quick overview of how to operate your oscillo-scope.

� The User Manual provides instructions on how to operate your oscilloscope.

� The Programmer Manual provides complete information on programmingand remote control of the oscilloscope through the GPIB.

xvi TDS 420A, TDS 430A & TDS 460A Service Manual

Introduction

This section contains general information critical to safe and effective servicingof this oscilloscope, the manual service strategy, and a description of repair andwarranty services available from Tektronix.

Before ServicingThis manual is for servicing the TDS 420A, TDS 430A, & TDS 460A DigitizingOscilloscopes. To prevent injury to yourself or damage to the oscilloscope, dothe following before you attempt service:

� Be sure you are a qualified service person.

� Read the safety summaries found at the beginning of this manual.

� Read Strategy for Servicing and Supplying Operating Power in this subsection.

When using this manual for servicing, be sure to heed all warnings, cautions, and notes.

STOP. If servicing a TDS 430A, follow the procedures for the TDS 420A, butignore all references to CH 3 and CH 4.

Strategy for Servicing

STOP. Throughout this manual, any field-replaceable component, assembly, orpart of this oscilloscope is referred to generically as a module.

This manual contains all the information needed for periodic maintenance ofyour oscilloscope. (Examples of such information are procedures for checkingperformance and for readjustment.) Further, it contains all information forcorrective maintenance down to the module level. This means that the proce-dures, diagrams, and other troubleshooting aids help isolate failures to a specificmodule, rather than to components of that module. Once a failure is isolated,replace the module with a fully tested module obtained from the factory.

All modules are listed in Chapter 10, Mechanical Parts List. To isolate a failureto a module, use the fault isolation procedures found in Chapter 6, Maintenance.

Introduction

TDS 420A, TDS 430A & TDS 460A Service Manual xvii

To remove and replace any failed module, follow the instructions in Removaland Installation Procedures, also found in Chapter 6.

Tektronix ServiceTektronix provides service to cover repair under warranty as well as otherservices that may provide a cost-effective answer to your service needs.

Whether providing warranty repair service or any of the other services listedbelow, Tektronix service technicians, trained on Tektronix products, are bestequipped to service your digitizing oscilloscope. Tektronix technicians areappraised of the latest information on improvements to the product as well as thelatest new options to the product.

Tektronix warrants this product for three years from date of purchase, excludingprobes for which the warranty is one year. (The warranty appears on the back ofthe title page in this manual.) Tektronix technicians provide warranty service atmost Tektronix service locations worldwide. Your Tektronix product catalog listsall service locations worldwide.

The following services may be purchased to tailor repair and/or calibration ofyour digitizing oscilloscope to fit your requirements.

Option 95. With this option, Tektronix ships a test data report for the oscilloscope.

At-Depot Service. Tektronix offers several standard-priced adjustment (calibra-tion) and repair services:

� A single repair or adjustment

� Calibrations using equipment and procedures that meet the traceabilitystandards specific to the local area

� Annual maintenance agreements that provide for either calibration and repairor calibration only of the oscilloscope

Of these services, the annual maintenance agreement offers a particularlycost-effective approach to service for many owners of the TDS 400A DigitizingOscilloscopes. You can purchase such agreements to span several years.

Tektronix supports repair to the module level by providing Module Exchangeand Module Repair and Return.

Warranty Repair Service

Repair or CalibrationService

Self Service

Introduction

xviii TDS 420A, TDS 430A & TDS 460A Service Manual

Module Exchange. This service reduces down time for repair by allowing you toexchange most modules for remanufactured ones. Tektronix ships you anupdated and tested exchange module from the Beaverton, Oregon service center,typically within 24 hours. Each module comes with a 90-day service warranty.

For More Information. Contact your local Tektronix service center or salesengineer for more information on any of the repair or adjustment services just described.

TDS 420A, TDS 430A & TDS 460A Service Manual 1–1

Product Description

This Chapter begins with a general description of the traits of the TDS 400ADigitizing Oscilloscopes. Three sections follow, one for each of three classes oftraits: nominal traits, warranted characteristics, and typical characteristics.

GeneralThe TDS 400A Digitizing Oscilloscopes are portable, four-channel instrumentssuitable for use in a variety of test and measurement applications and systems.Table 1–1 lists key features.

Table 1–1: Key Features of the TDS 400A Oscilloscopes

Feature Description

Digitizing rate, maximum 100 MS/s on each channel simultaneously

Analog bandwidth TDS 460A: 400 MHz

TDS 420A: 200 MHz

TDS 430A: 400 MHz

Channels TDS 460A: Four, each with 8-bit resolution

TDS 420A: Four, each with 8-bit resolution

TDS 430A: Two, each with 8-bit resolution

Record lengths, maximum 30,000 samples (120,000 with option 1M)

Acquisition modes Sample, envelope, average, high-resolution, and peak-detect

Trigger modes Edge With Option 05, video trigger modes include:NTSC, SECAM, PAL, and Custom

Display Modes Infinite and variable persistence, roll, fit to screen, and dualwaveform zoom

Storage A 1.44 Mbyte, 3.5 inch, DOS 3.3-or-later floppy disk andNVRAM storage for saving waveforms, hardcopies, and setups

I/O Full GPIB programmabilityHardcopy output using GPIB and, with Option 13, RS-232 orCentronics ports

Math Including: invert, add, subtract, multiply, and with Option 2F,integral, differential, and FFT

User interface A graphical user interface, on-line help. and a logicalfront-panel layout

Product Description

1–2 TDS 420A, TDS 430A & TDS 460A Service Manual

User InterfaceThis digitizing oscilloscope uses a combination of front-panel buttons, knobs,and on-screen menus to control its many functions. The front-panel controls aregrouped according to function: vertical, horizontal, trigger, and special. Withineach group, any function likely to get adjusted often, such as vertical positioningor the time base setting, is set directly by its own front-panel knob.

Those functions for which control settings are usually changed less often, such asvertical coupling and horizontal mode, are set indirectly. That is, pressing one(sometimes two) front-panel button, such as VERTICAL, displays a menu offunctions at the bottom of the screen that are related to that button. (For theVERTICAL button, the menu displayed contains functions such as coupling andbandwidth.) Using the buttons below this main menu to select a function, such ascoupling, displays a side menu of settings for that function, such as AC, DC, orGND (ground) coupling, at the right side of the screen. Use the buttons to theright of the menu to select a setting, such as DC.

Several on-screen readouts help you keep track of the settings for variousfunctions, such as vertical and horizontal scale and trigger level. There are alsoreadouts to display the results of measurements made using cursors or using theautomatic parameter extraction feature (called measure) and readouts to displaythe status of the oscilloscope.

Menus are also used to assign the general purpose knob to adjust a selectedparameter function. The method employed is the same as for selecting afunction, except the final selection in the side menu causes the general purposeknob to adjust some function, such as the position of measurement cursors onscreen or the setting for the fine gain of a channel.

The user interface also makes use of a GUI, or Graphical User Interface, to makesetting functions and interpreting the display more intuitive. Some menus andstatus are displayed using iconic representations of function settings such asthose shown here for full, 100 MHz, and 20 MHz bandwidth. Such icons allowyou to more readily determine status or the available settings.

Menus

Indicators

General Purpose Knob

GUI

Product Description


Signal Acquisition SystemThe signal acquisition system provides vertical channels with calibrated verticalscale factors from 1 mV to 10 V per division. All input channels can be acquiredsimultaneously.

You can display, vertically position, and offset each input channel. You can alsolimit their bandwidth (to either 100 MHz or 20 MHz), specify their verticalcoupling, and adjust their fine gain.

Besides the input channels, up to three math waveforms and four referencewaveforms are available for display. (A math waveform results when you specifyoperations such as add or invert; a reference waveform results when you save alive waveform in a reference memory.)

Horizontal SystemThere are three horizontal display modes: main only, main intensified, anddelayed only. You can select among various horizontal record length settings (seeTable 1–2).

Table 1–2: Record Length vs. Divisions per Record

Record Length1, 2Divisions per Record(50 Points/Division)

120,000 2400 divs

60,000 1200 divs

30,000 600 divs

15,000 300 divs

5,000 100 divs

2,500 50 divs

1,000 20 divs

500 10 divs1 The 60,000 and 120,000 point record lengths are available

only with Option 1M.2 If you select the Hi Res acquisition mode, the maximum

Option 1M record length reduces to 60,000 points.

Product Description


Both the delayed only display and the intensified zone on the main intensifieddisplay can be delayed by time with respect to the main trigger. You can set bothto display immediately after the delay (delayed runs after main mode); you canset the delayed display to display at the first valid trigger after the delay (delayedtriggerable mode).

The delayed display (or the intensified zone) can also be delayed by a selectednumber of events. In such a case, the events source is the delayed trigger source.For any events signal, the delayed-trigger system conditions the signal bydetermining the source, coupling, and other things, of that signal.

At time base settings of 20 ms per division or slower the records are displayableusing Roll mode. Both untriggered roll and triggered roll modes are available.

Trigger SystemThe triggering system comprises a complete set of features for triggering thesignal-acquisition system. In edge trigger mode, you can select the source, slope,coupling, mode (auto or normal), and holdoff.

Oscilloscopes ordered with Option 5 also have the video trigger mode. Thistrigger mode allows triggering on NTSC-standard, PAL-standard, SECAM-stan-dard, and custom video waveforms. You can configure the triggering forinterlaced or non-interlaced scanning, different scan rates, field selection, lineselection, and for delay by line or time.

You can choose where the trigger point is located within the acquired waveformrecord by selecting the amount of pretrigger data displayed. You can selectpresets of 10%, 50%, and 90% of pretrigger data in the horizontal menu, or youcan assign the General Purpose knob to set pretrigger data to any value withinthe limits of trigger position resolution.

Acquisition ControlDepending on your measurement requirements, you can specify the mode andmanner in which signals are acquired and processed:

� You can select equivalent-time sampling on repetitive signals or interpola-tion of points sampled on non-repetitive signals. Both can increase theapparent sample rate on the waveform when maximum real-time rates arereached.

� You can use peak-detect, high-resolution, sample, envelope, and averagemodes to acquire signals.

� You can set the acquisition to stop after a single acquisition (or sequence ofacquisitions if acquiring in average or envelope modes).

Product Description


On-Board User AssistanceTwo features that help you set up this digitizing oscilloscope to make yourmeasurements are help and autoset.

Help displays operational information about any front-panel control. When helpmode is in effect, manipulating any front-panel control causes the digitizingoscilloscope to display information about that control. When help is firstinvoked, an introduction to help is displayed on screen.

Autoset automatically sets up the digitizing oscilloscope for a viewable displaybased on the input signal.

Measurement AssistanceOnce you have set up to make your measurements, the features cursor andmeasure can help you quickly make those measurements.

Two types of cursors are provided for making parametric measurements on thedisplayed waveforms. Voltage can be measured between the positions of H Bar(horizontal) cursors, and time can be measured between V Bar (vertical) cursors.These are delta measurements; that is, measurements based on the differencebetween two cursors.

You can use both V Bar and H Bar cursors to make absolute measurements—measurements relative to a defined level or event. In the case of the H Bars,either cursor can be selected to read out its voltage with respect to the groundreference level of any channel; in the case of the V Bars, its time with respect tothe trigger point (event) of the acquisition.

For time measurements, units can be either base (seconds or clocks) or inversebase (Hertz or 1/clocks).

Measure can automatically extract parameters from the signal input to thedigitizing oscilloscope. Any four out of the more than 20 parameters availablecan be displayed on the screen. The displayed parameters are extracted continu-ously and the results updated on screen as the digitizing oscilloscope continuesto acquire waveforms.

Help

Autoset

Cursor

Measure

Product Description


StorageTDS 400A Digitizing Oscilloscopes can save acquired waveforms in any of fournonvolatile REF (reference) memories. You can save any input-channelwaveform to any REF memory, or you can move a stored reference from oneREF memory to another. You can display any or all of the saved waveforms forcomparison with the waveforms being currently acquired.

I/OTDS 400A Digitizing Oscilloscopes are fully controllable and capable of sendingand receiving waveforms over the GPIB interface (IEEE Std 488.1-1987/IEEEStd 488.2-1987 standard). Self-compensation and self-diagnostic features builtinto the digitizing oscilloscope to aid in fault detection and servicing are alsoaccessible using commands sent from a GPIB controller. The oscilloscope alsoprovides the following output capabilities:

� Output of the current oscilloscope screen, including waveforms, to a varietyof graphic printers and plotters to obtain hard copies. You can start ahardcopy from the oscilloscope front panel; you are not required to connectinto a system-controller environment. The hard copies obtained areWYSIWYG (What-You-See-Is-What-You-Get), based on what is displayedat the time hardcopy is invoked.

� Output of display hard copies, of oscilloscope control setups, and ofwaveforms to a floppy disk in the oscilloscope file system.

� Output of the oscilloscope display for monitoring (or other processing) froma VGA-compatible video output on the oscilloscope rear panel.

DisplayThe TDS 400A Digitizing Oscilloscopes offer flexible display options. You cancustomize the following attributes of your display:

� Intensity: waveforms, readouts, graticule, and other things

� Style of waveform display(s): vectors or dots, intensified or non-intensifiedsamples, and infinite or variable persistence

� Display format: XY or YT and graticule type

This digitizing oscilloscope also provides an easy way to focus in on thosewaveform features you wish to examine up close. By using ZOOM, you canmagnify the waveform parameter using the vertical and horizontal controls toexpand (or contract) and position it for viewing.


Nominal Traits

Nominal traits are described using simple statements of fact such as “Four, allidentical” for the trait “Input Channels, Number of,” rather than in terms oflimits that are performance requirements.

Table 1–3: Nominal Traits — Signal Acquisition System

Name Description

Bandwidth Selections 20 MHz, 100 MHz, and FULL (TDS 420A: 200 MHz, TDS 430A andTDS 460A: 400 MHz)

Digitizers, Number of TDS 430A: Two, both identicalTDS 420A and TDS 460A: Four, all identical

Digitized Bits, Number of 8 bits1

Digitized Resolution, Hi Res Mode Clock, Internal:

Clock, External:

ResolutionHiRes � 8 � �8 � 0.5 Log2� time�div500 � 10–9

� � 15 bits

ResolutionHiRes � 8 � �8 � 0.5 Log2� 100, 000, 000ClockExternalMenu

� � 11.8 bits

Bandwidth, Hi Res Mode Clock, Internal:

Clock, External:

For 1�s�div and slower, BWHiRes � 0.44 � � 50time�div

Hz

BWHiRes � 44 � �ClockExternalMenu100

Hz

Input Channels, Number of TDS 430A: Two, both identical, called CH 1 and CH 2TDS 420A and TDS 460A: Four, all identical, called CH 1 through CH 4

Input Coupling DC, AC, or GND2

Input Resistance Selections 1 M� or 50�

Ranges, Offset, All Channels Volts/Div Setting Offset Range

1 mV/div to 99.5 mV/div ±1 V

100 mV/div to 995 mV/div ±10 V

1 V/div to 10 V/div ±100 V

Range, Position ±5 divisions

Range, Sensitivity3 1 mV/div to 10 V/div

Nominal Traits


Table 1–3: Nominal Traits — Signal Acquisition System (Cont.)

Name Description

Rise Time4

AVolts/Div Setting Rise Time

(TDS420A) 5 mV/div–10 V/div 1.75 ns

2 mV/div–4.98 mV/div 2.33 ns


Rise Time4

A AVolts/Div Setting Rise Time

(TDS 430A and TDS 460A) 5 mV/div–10 V/div 875 ps


1 mV/div–1.99 mV/div 3.5 ns1 Displayed vertically with 25 digitization levels (DLs) per division and 10.24 divisions dynamic range with zoom off. A DL

is the smallest voltage level change resolved by the 8-bit A-D Converter with the input scaled to the volts/division settingof the channel used. Expressed as a voltage, a DL is equal to 1/25 of a division times the volts/division setting.

2 GND input coupling disconnects the input connector from the attenuator and connects a ground reference to the input ofthe attenuator.

3 The sensitivity ranges from 1 mV/div to 10 V/div in a 1–2–5 sequence of coarse settings. Between consecutivecoarse settings, the sensitivity can be finely adjusted with a resolution of 1% of the more sensitive setting. Forexample, between 50 mV/div and 100 mV/div, the volts/division can be set with 0.5 mV resolution.

4 Rise time is defined by the following formula: Rise Time (ns) � 420BW (MHz)

Nominal Traits


Table 1–4: Nominal Traits — Time Base System

Name Description

Range, Sample-Rate1,3 2.5 Samples/s to 100 MSamples/s

Range, Equivalent Time or InterpolatedWaveform Rate2,3

200 MSamples/s to 50 GSamples/s

Range, Seconds/Division 1 ns/div to 20 s/div

Range, Time Base Delay Time 0 to 20 seconds

Reference Frequency, Time Base 100 MHz

Record Length Selection 500, 1,000, 2,500, 5,000, 15,000, and 30,000 points. Record lengths of 60,000 and120,000 points are available with Option 1M4

Sampling Edge, External Clock Negative edge, with TTL threshold and tolerances

Hi Res Averaging Period, External Clock Hi Res averaging done over period 1/(maximum external clock rate5), but within <100 nsto 2 �s. An external clock edge before this period ends produces an invalid sample.

1 The range of real-time rates, expressed in samples/second, at which a digitizer samples signals at its inputs andstores the samples in memory to produce a record of time-sequential samples.

2 The range of waveform rates for equivalent time or interpolated waveform records.3 The Waveform Rate (WR) is the equivalent sample rate of a waveform record. For a waveform record acquired by

real-time sampling of a single acquisition, the waveform rate is the same as the real-time sample rate; for awaveform created by interpolation of real-time samples from a single acquisition or by equivalent-time sampling ofmultiple acquisitions, the waveform rate is faster than the real time sample rate. For all three cases, the waveformrate is 1/(Waveform Interval) for the waveform record, where the waveform interval (WI) is the time between thesamples in the waveform record.

4 In Hi Res, the maximum Option 1M record length is 60,000 points.5 You set the maximum external clock rate using the Horizontal Clock menu. The Hi Res samples are averaged over a

10 to 40 ns shorter period than shown by the readout.

Table 1–5: Nominal Traits — Triggering System

Name Description

Range, Events Delay 1 to 9,999,999

Ranges, Trigger Level or Threshold Source Range

Any Channel ±12 divisions from center of screen

Line ±400 Volts

Nominal Traits


Table 1–6: Nominal Traits — Display System

Name Description

Video Display Resolution 640 pixels horizontally by 480 pixels vertically in a display area of 5.04 inches horizontallyby 3.78 inches vertically

Waveform Display Graticule A single graticule 401 × 501 pixels (8 × 10 divisions, with divisions that are 1 cm by1 cm)

Waveform Display Grey Scale 16 levels in variable-persistence display style

Table 1–7: Nominal Traits — Data Storage

Name Description

Capacity, Nonvolatile Waveform Memory Total capacity is 120,000 points (one to four waveforms acquired with any combination ofrecord lengths that add up to 120,000 points). For available record lengths, see RecordLength Selection on page 1–9 of this chapter.

Capacity, Nonvolatile Setup Memory Ten setups

Batteries1 Required Two lithium poly-carbon monofluoride. Both are type BR2/3A, UL listed. Both are rated at3.0 volt, 1.2 amp-hour.

1 Batteries are not accessible from the outside of the instrument; therefore, a service technician must replace them.

Table 1–8: Nominal Traits — GPIB Interface, Video Output, and Power Fuse

Name Description

Interface, GPIB GPIB interface complies with IEEE Std 488.1-1987 and IEEE Std 488.2-1987.

Interface, RS-232 (Option 13 only) RS-232 interface complies with EIA/TIA 574.

Interface, Centronics (Option 13 only) Centronics interface complies with Centronics interface standard C332-44 Feb 1977,REV A.

Power Supply, Printer (Option 13 only) Supply Voltage: +6.5 VDC

Maximum Current: 2 Amps, DC continuous4 Amps DC maximum for durations < 10 msec

Output, Video Provides a video signal1, non-interlaced, with levels that comply with ANSI RS343A.Output is through a rear-panel DB-15 connector.

Fuse Rating Either of two fuses2 may be used: a 0.25� × 1.25� (UL 198.6, 3AG): 5 A FAST, 250 V, ora 5 mm × 20 mm, (IEC 127): 4 A (T), 250 V.

1 VGA compatible at 30.6 kHz sync rate.

2 Each fuse type requires its own fuse cap.

Nominal Traits


Table 1–9: Nominal Traits — Mechanical

Name Description

Cooling Method Forced-air circulation with no air filter

Construction Material Chassis parts constructed of aluminum alloy; front panel constructed of plastic laminate;circuit boards constructed of glass-laminate. Plastic parts are polycarbonate.

Finish Type Tektronix Blue textured vinyl finish on aluminum cabinet

Weight Standard digitizing oscilloscope

8.6 kg (19.0 lbs), oscilloscope only

10.2 kg (22.5 lbs), with front cover, accessories, and accessories pouch installed

14.5 kg (32.0 lbs), when packaged for domestic shipment

225 grams (0.5 lbs) Floppy Disk Drive only

Rackmount digitizing oscilloscope

8.2 kg (18.0 lbs) plus the weight of rackmount parts, for the rackmounted digitizingoscilloscope (Option 1R)

16.3 kg (36.0 lbs), when the rackmounted digitizing oscilloscope is packaged fordomestic shipment

Rackmount conversion kit

4.5 kg (10.0 lbs), parts only; 7.9 kg (17.5 lbs), parts plus package for domestic shipping

Nominal Traits


Table 1–9: Nominal Traits — Mechanical (Cont.)

Name Description

Overall Dimensions Standard digitizing oscilloscope

Height 191 mm (7.5 in), when feet and accessories pouch are installed. 165 mm(6.5 in), without the accessories pouch installed

Width 381 mm (15 in), with handle

Depth 471 mm (18.55 in), oscilloscope only; 490 mm (19.28 in), with optionalfront cover installed; 569 mm (22.4 in), with handle fully extended

Rackmount digitizing oscilloscope

Height 178 mm (7.0 in)

Width 483 mm (19.0 in)

Depth 472 mm (18.6 in), without front-panel handles; 517 mm (20.35 in), withfront-panel handles installed

Nominal Traits


327.2 mm(12.88 in.)

471 mm(18.55 in.)

381 mm(15 in.)

165 mm(6.5 in.)

308.1 mm(12.13 in.)

569 mm(22.4 in.)

Figure 1–1: TDS 400A Dimensional Drawing

Nominal Traits



Warranted Characteristics

This section lists the various warranted characteristics that describe theTDS 400A Digitizing Oscilloscopes. Included are electrical and environmental characteristics.

Warranted characteristics are described in terms of quantifiable performancelimits which are warranted. This section lists only warranted characteristics. Alist of typical characteristics starts on page 1–21.

NOTE. In these tables, those warranted characteristics that are checked in theprocedure Performance Tests, on page 4–15, appear in boldface type under thecolumn Name.

Performance ConditionsThe electrical characteristics found in these tables of warranted characteristicsapply when the oscilloscope is adjusted at an ambient temperature between+20� C and +30� C, has had a warm-up period of at least 20 minutes, and isoperating at an ambient temperature between 0� C and +50� C (unless otherwise noted).

Table 1–10: Warranted Characteristics — Signal Acquisition System

Name Description

Accuracy, DC Voltage Mea-ure e , Averaged

Measurement Type DC Accuracysurement, Averaged Average of ≥16 waveforms ±(1.5% × | (reading – Net Offset1)| + Offset Accuracy +

0.06 div × Vertical Scale)

Delta volts between any twoaverages of ≥16 waveforms2

±(1.5% × |reading| + 0.3 mV + 0.1 div × Vertical Scale)

Accuracy, DC Gain3 ±1.5%

Accuracy, Offset Volts/Div Setting Offset Accuracy

1 mV/div–9.95 mV/div ±(0.4% × |Net Offset1| + ( 0.9 mV + 0.1 div × Vertical Scale))

10 mV/div–99.5 mV/div ±(0.4% × |Net Offset1| + (1.5 mV + 0.1 div × Vertical Scale))

100 mV/div–995 mV/div ±(0.4% × |Net Offset1| + ( 15 mV + 0.1 div × Vertical Scale))

1 V/div–10 V/div ±(0.4% × |Net Offset1| + (150 mV + 0.1 div × Vertical Scale)

Accuracy, Position4 ±(1.5% × (Position × Volts/div) + Offset Accuracy + 0.04 div)



Table 1–10: Warranted Characteristics — Signal Acquisition System (Cont.)

Name Description

Analog Bandwidth, DC-50 �Coupled to BNC and Band-

id h Selec i i ullVolts/Div

TDS 420A Bandwidth5

TDS 430A and TDS 460A Bandwidth5

width Selection is Full 5 mV/div–10 V/div DC–200 MHz DC–400 MHz

2 mV/div–4.98 mV/div DC–150 MHz DC–250 MHz


Cross Talk (Channel Isolation) Volts/Div Isolation

�500 mV/div ≥40:1 at 50 MHz for any two channels having equal volts/divisionsettings

≤9.95 mV/div ≥40:1 at 50 MHz for any two channels having equal volts/divisionsettings

10 mV/div–500 mV/div ≥80:1 at 100 MHz and ≥30:1 at full bandwidth for any twochannels having equal volts/division settings

Delay Between Channels, FullBandwidth, Equivalent Time

≤200 ps between CH 1 and CH 2 and between CH 3 and CH 4 when both channels have equalvolts/division and coupling settings

≤450 ps for any other combination of two channels with equal volts/division and coupling settings

Input Impedance, DC-1 M�Coupled

1 M� ±0.5% in parallel with 15 pF ±2.0 pF. Matched between channels to within ±1% for resistanceand ±1.0 pF for capacitance

Input Impedance, DC-50�Coupled(TDS 420A)

50 � ±1% with VSWR ≤1.2:1 from DC–200 MHz

Input Impedance, DC-50�Coupled(TDS 430A and TDS 460A)

50 � ±1% with VSWR ≤1.6:1 from DC–400 MHz

Input Voltage, Maximum,C � AC � or N

Volt/Div ��DC-1 M�, AC-1 M�, or GNDCoupled

0.1 V/div–10 V/div 300 V CAT II; derate at 20 dB/decade above 10 MHz until theminimum rating of ±5 V (DC + peak AC) is reached

1 mV/div–99.9 mV/div 300 V CAT II; derate at 20 dB/decade above 10 kHz until theminimum rating of ±5 V (DC + peak AC) is reached

Input Voltage, Maximum,DC-50� or AC-50� Coupled

5 VRMS, with peaks less than or equal to ±30 V



Table 1–10: Warranted Characteristics — Signal Acquisition System (Cont.)

Name Description

Lower Frequency Limit, ACCoupled

≤10 Hz when AC–1 M� coupled; ≤200 kHz when AC-50� coupled6

1 Net Offset = Offset – (Position × Volts/Div). Net Offset is the voltage level at the center of the A-D converter dynamicrange. Offset Accuracy is the accuracy of this voltage level.

2 The samples must be acquired under the same setup and ambient conditions.3 DC Gain Accuracy is confirmed in the Performance Verification Procedure by passing the checks for Offset Accuracy and

DC Voltage Measurement Accuracy (Averaged).4 Position Accuracy is confirmed in the Performance Verification Procedure by passing the checks for Offset Accuracy and

DC Voltage Measurement Accuracy (Averaged).5 The limits given are for the ambient temperature range of 0� C to +30� C. Reduce the upper bandwidth frequencies by

2.5 MHz for each �C above +30� C.6 The AC Coupled Lower Frequency Limits are reduced by a factor of 10 when 10X, passive probes are used.

Table 1–11: Warranted Characteristics — Time Base System

Name Description

Accuracy, Long Term Sample Rate andDelay Time

±150 ppm over any ≥1 ms interval

Accuracy, Absolute Time and Delay TimeMeasurements1,2

For single-shot acquisitions using sample or high-resolution acquisition modes and abandwidth limit setting of 100 MHz:

±(1 WI + 150 ppm of |Reading| + 450 ps)


±(1 WI + 150 ppm of |Reading| + 1.3 ns)

For repetitive acquisitions using average acquisition mode with ≥8 averages and abandwidth limit setting of FULL:


Accuracy, Delta Time Measurement1, 2



For repetitive acquisitions using average acquisition mode with ≥8 averages and abandwidth limit setting of FULL:

±(1 WI + 150 ppm of |Reading| + 300 ps)1 For input signals ≥ 5 divisions in amplitude and a slew rate of ≥ 2.0 divisions/ns at the delta time measurement

points. Signal must have been acquired at a volts/division setting ≥ 5 mV/division and not in Events mode.2 The WI (waveform interval) is the time between the samples in the waveform record. Also, see the footnotes for

Sample Rate Range and Equivalent Time or Interpolated Waveform Rates in Table 1–4 on page 1–9.



Table 1–12: Warranted Characteristics — Triggering System

Name Description

Accuracy, Trigger Level or Threshold,DC Coupled

±(2% of |Setting – Net Offset1| + 0.2 div × volts/div setting + Offset Accuracy) for anychannel as trigger source and for signals having rise and fall times ≥ 20 ns

Sensitivity, Edge-Type Trigger, DCCoupled2

0.35 division from DC to 50 MHz, increasing to 1 division at 350 MHz (TDS 420A) or500 MHz (TDS 430A and TDS 460A) for any channel as trigger source

Sensitivity, Video-Type, TV Field and TVLine2

0.6 division of video sync signal

Pulse Width, minimum, Events-Delay 5 ns

Auxiliary Trigger Input, External Clock Input Connector: BNC at rear panel

Input Load: equivalent to three TTL gate loads

Input Voltage (maximum): –5 VDC to +10 VDC (TTL levels recommended)

Auxiliary Trigger, Maximum InputFrequency

10 MHz

Duty Cycle High and low levels must be stable for ≥ 50 ns

Frequency, External Clock DC to 10 MHz High and low levels must be stable for ≥ 50 ns1 Net Offset = Offset – (Position × Volts/Div). Net Offset is the voltage level at the center of the A-D converter dynamic

range. Offset Accuracy is the accuracy of this voltage level.2 The minimum sensitivity for obtaining a stable trigger. A stable trigger results in a uniform, regular display triggered on

the selected slope. The trigger point must not switch between opposite slopes on the waveform, and the display must not“roll” across the screen on successive acquisitions. The TRIG’D LED stays constantly lighted when the SEC/DIV settingis 2 ms or faster but may flash when the SEC/DIV setting is 10 ms or slower.

Table 1–13: Warranted Characteristics — Probe Compensator Output

Name Description

Output Voltage and Frequency,Pr be pe a r

Characteristic LimitsProbe Compensator Voltage 0.5 V (base-top) ±5% into a 1 M� load

Frequency 1 kHz ±5%

Table 1–14: Warranted Characteristics — Power Requirements

Name Description

Source Voltage and Frequency 90 to 132 VACRMS CAT II, continuous range, for 48 Hz through 62 Hz

100 to 132 VACRMS CAT II, continuous range, for 48 Hz through 440 Hz

180 to 250 VACRMS CAT II, continuous range, for 48 Hz through 440 Hz

Power Consumption ≤240 Watts (370 VA)



Table 1–15: Warranted Characteristics — Environmental, Safety, and Reliability

Name Description

Atmospherics Temperature1:

Operating, +0� C to +50� C (disk drive operation limited to +4� C minimum); Nonoperating, –22� C to +60� C

Relative humidity:

Operating without disk, to 80%, at or below +29� C; to 20%, at or below +50� C;Operating with disk, 20% (+4� C to +50� C) to 80% (+4� C to +29� C) ; Nonoperating, 20% (+4� C to +60� C) to 90% (+22� C to +40� C)

Altitude:

Operating, to 15,000 ft. (4570 m); Nonoperating, to 40,000 ft. (12190 m)

1 Maximum operating temperature is decreased 1� C per 1000 feet (305 meters) above 5000 feet (1525 meters).



Table 1–16: Certifications and compliances

EC Declaration of Conformity1,2 Meets intent of Directive 89/336/EEC for Electromagnetic Compatibility and Low Voltage Directive73/23/ECC for Product Safety. Compliance was demonstrated to the following specifications aslisted in the Official Journal of the European Communities:

EN 50081-1 Emissions:EN 55022 Class B Radiated and Conducted Emissions

EN 50082-1 Immunity:IEC 801-2 Electrostatic Discharge ImmunityIEC 801-3 RF Electromagnetic Field ImmunityIEC 801-4 Electrical Fast Transient/Burst ImmunityIEC 801-5 Power Line Surge Immunity

Low Voltage Directive 73/23/EEC:EN 61010-1 Safety requirements for electrical equipment for measurement,

control, and laboratory use

FCC Compliance Emissions comply with FCC Code of Federal Regulations 47, Part 15, Subpart B, Class A Limits

Certifications Underwriters Laboratories certified to Standard UL3111-1 for Electrical Measuring and TestEquipment.

Canadian Standards Association certified to Standard CAN/CSA-C22.2 No. 1010.1-92, SafetyRequirements for Electrical Equipment for Measurement, Control, and Laboratory Use.

Temperature (operating) +0� C to +50� C

Altitude (maximum operating) 2000 meters

Safety Class Class I (as defined in IEC 1010–1, Annex H) – grounded product

CSA Certified Power Cords CSA Certification includes the products and power cords appropriate for use in the North Americapower network. All other power cords supplied are approved for the country of use.

Overvoltage Category Category: Examples of Products in this Category:

CAT I Signal levels in special equipment or parts of equipment, telecommu-nications, electronics

CAT II Local-level mains, appliances, portable equipment

CAT III Distribution-level mains, fixed installation

Pollution Degree 2 Do not operate in environments where conductive pollutants may be present.1 To maintain emission requirements when connecting to the IEEE 488 GPIB interface of this oscilloscope, use only a

high-quality, double-shielded (braid and foil) GPIB cable. The cable shield must have low impedance connections to bothconnector housings. Acceptable cables are Tektronix part numbers 012-0991-00, -01, -02 and -03. To maintain EMIperformance use the following cables, or their equivalent: a shielded Centronics cable, 3 meters long, part number012-1214-00, and a shielded RS-232 cable, 2.7 meters long, CA part number 0294-9.

2 To maintain emission requirements when connecting to the VGA-compatible video output of this oscilloscope, use only ahigh-quality double-shielded (braid and foil) video cable with ferrite cores at both ends. The cable shield must have lowimpedance connections to both connector housings. An acceptable cable is LCOM part number CTL3VGAMM-5.


Typical Characteristics

This section contains tables that list the various typical characteristics thatdescribe the TDS 400A Digitizing Oscilloscopes.

Typical characteristics are described in terms of typical or average performance.Typical characteristics are not warranted.

This subsection lists only typical characteristics. A list of warranted characteris-tics starts on page 1–15.

Table 1–17: Typical Characteristics — Signal Acquisition System

Name Description

Accuracy, DC Voltage Measurement,Not Aver e

Measurement Type DC AccuracyNot Averaged Any Sample ±(1.5% × (|reading – Net Offset1|) + Offset

Accuracy + 0.13 div + 0.6 mV)

Delta Volts between any two sam-ples2

±(1.5% × |reading| + 0.26 div + 1.2 mV)

Frequency Limit, Upper, 100 MHz Band-width Limited

100 MHz

Frequency Limit, Upper, 20 MHz Band-width Limited

20 MHz

Nonlinearity �1 DL, differential; ≤ 1 DL, integral, independently based3

Analog Bandwidth, DC-1 M� Coupled withStandard-Accessory Probe Attached

Volts/Div TDS 420ABandwidth

TDS 430A and TDS 460ABandwidtht r Accessor Pro e Att c e

5 mV/div–10 V/div DC–200 MHz DC–400 MHz





Table 1–17: Typical Characteristics — Signal Acquisition System (Cont.)

Name Description

Step Response Settling Error Volts/Div Setting Step Ampli-tude

Settling Error (%)4

20 ns 500 ns 20 ms

1 mV/div–99.5 mV/div ≤2 V ≤0.5 ≤0.2 ≤0.1

100 mV/div–995 mV/div ≤20 V ≤2.0 ≤0.5 ≤0.2

1 V/div–10 V/div ≤200 V ≤2.0 ≤0.5 ≤0.21 Net Offset = Offset – (Position x Volts/Div). Net Offset is the voltage level at the center of the A-D converter dynamic

range. Offset Accuracy is the accuracy of this voltage level.2 The samples must be acquired under the same setup and ambient conditions.3 A DL (digitization level) is the smallest voltage level change that can be resolved by the 8-bit A-D Converter with the input

scaled to the volts/division setting of the channel used. Expressed as a voltage, a DL is equal to 1/25 of a division timesthe volts/division setting.

4 The values given are the maximum absolute difference between the value at the end of a specified time interval after themid-level crossing of the step and the value one second after the mid-level crossing of the step, expressed as apercentage of the step amplitude.

Table 1–18: Typical Characteristics — Time Base System

Name Description

Aperture Uncertainty For real-time or interpolated records having duration ≤1 minute:

≤(50 ps + 0.03 ppm × Record Duration) RMS

For equivalent time records:

≤(50 ps + 0.06 ppm × WI1) RMS

Fixed Error in Sample Time ≤50 ps

External Clock sampling uncertainty ±8 ns

External Clock Edge to Sampling TimeDelay

Sample –20 ns (Sample edge is delayed relative the the sample moment.)

Hi Res Hi Res averaging starts within �8 ns of the clock edge. Averaging stops after 1/(maximum external clock rate2)

Peak Detect Runs continuously at 100 MS/s

External Clock Minimum Prerecord points 55 points before the first visible sample in the record at the maximum clock speed

35 points before the first visible sample in the record at slow clock speeds

External Clock Minimum Postrecord points 25 points after the last visible sample in the record1 The WI (waveform interval) is the time between the samples in the waveform record. Also, see the footnotes for

Sample Rate Range and Equivalent Time or Interpolated Waveform Rates in Table 1–4 on page 1–9.2 You set the maximum external clock rate using the Horizontal Clock menu.



Table 1–19: Typical Characteristics — Triggering System

Name Description

Error, Trigger Position, Edge Triggering Acquire Mode Trigger-Position Error1,2

Sample, Hi-Res, Average ±(1 WI + 1 ns)

Peak Detect, Envelope ±(2 WI + 1 ns)

Holdoff, Variable, Main Trigger, InternalCloc o ri er

Main Horizontal Scale Minimum Holdoff Maximum HoldoffClock and non TV Trigger ≤100 ns/div 1 �s 5 × Min Holdoff

≥100 ms/div 1 s 5 × Min Holdoff

Otherwise 10 × sec/div 5 × Min Holdoff

Holdoff, Variable, External Clock 0 to 100 ms

Auto Trigger Operation, External Clock Auto triggers 2 s after the last normal trigger or appropriated trigger mode is entered

Lowest Frequency for Successful Opera-tion of “Set Level to 50%” Function

20 Hz

Sensitivity, Edge Trigger, Not DC Coupled3 Trigger Coupling Typical Signal Level for Stable Triggering

AC Same as DC-coupled limits4 for frequencies above60 Hz. Attenuates signals below 60 Hz

Noise Reject Three and one-half times the DC-coupled limits 4

High Frequency Reject One and one-half times the DC-coupled limits4 fromDC to 30 kHz. Attenuates signals above 30 kHz

Low Frequency Reject One and one-half times the DC-coupled limits4 forfrequencies above 80 kHz. Attenuates signals below80 kHz

Video Mode (Option 05 Equipped Instru-ments Only)

Line Rate Class: Four classes are provided as follows

� NTSC, which provides a default line rate compatible with the NTSC standard(525/60)

� PAL, which provides a default line rate compatible with the PAL standard (625/50)

� SECAM, which provides a default line rate compatible with the SECAM standard(625/50)

� Custom, which provides user selectable line rate ranges (see Custom Line RateRanges below)

Custom Line Rate Ranges: 15 kHz–20 kHz, 20 kHz–25 kHz, 25 kHz–35 kHz, and35 kHz–64 kHz

Holdoff: Automatically adjusts to 58 ms (nominal) for NTSC class; to 150 ms (nominal) forPAL and SECAM. A holdoff of 0 to 100 typically covers a range of 1 to 400 ms

Triggerable on Field Selections: Odd, Even, or Both

Delayed Acquisition: Settable for delay by line number or runs after time delay

Frequency, Maximum for Events Delay5 90 MHz



Table 1–19: Typical Characteristics — Triggering System (Cont.)

Name Description

Width, Minimum Pulse and Rearm, EventsDelay6

5 ns

1 The trigger position errors are typically less than the values given here. These values are for triggering signals having aslew rate at the trigger point of ±0.5 division/ns.

2 The waveform interval (WI) is the time between the samples in the waveform record. Also, see the footnote for thecharacteristics Sample Rate Range and Equivalent Time or Interpolated Waveform Rates in Table 1–4 on page 1–9.

3 The minimum sensitivity for obtaining a stable trigger. A stable trigger results in a uniform, regular display triggered onthe selected slope. The trigger point must not switch between opposite slopes on the waveform, and the display must not“roll” across the screen on successive acquisitions. The TRIG’D LED stays constantly lighted when the SEC/DIV settingis 2 ms or faster but may flash when the SEC/DIV setting is 10 ms or slower.

4 See the characteristic Sensitivity, Edge-Type Trigger, DC Coupled in Table 1–12, which begins on page 1–18.

5 The maximum frequency for a delaying events input.

6 The minimum pulse width and rearm width required for recognizing a delaying event.

Table 1–20: Typical Characteristics — Data Handling

Name Description

Time, Data-Retention, NonvolatileMemory1,2

Internal batteries, installed at time of manufacture, have a life of ≥5 years when operatedand/or stored at an ambient temperature from 0� C to 50� C. Retention time of thenonvolatile memories is equal to the remaining life of the batteries

Nonvolatile Memory Save Time 10 seconds

Floppy Disk Drive Capacity 3.5 in. floppy disk, 720 KB or 1.44 MB, compatible with DOS 3.3 format for storingwaveforms, hard copies, and instrument setups

1 The time that reference waveforms, stored setups, and calibration constants are retained when there is no power to theoscilloscope.

2 Data is maintained by lithium poly-carbon monofluoride.


Installation

This chapter contains information about supplying operating power, theoperating environment, applying and interrupting power, repackaging forshipment, and installed options.

Supplying Operating Power

STOP. Read all information and heed all warnings in this chapter beforeconnecting the digitizing oscilloscope to a power source.

WARNING. AC POWER SOURCE AND CONNECTION. The digitizing oscillo-scope operates from a single-phase power source. It has a three-wire power cordand a two-pole three-terminal grounding type plug. The voltage to ground(earth) from either pole of the power source must not exceed the 250 VRMSmaximum rated operating voltage.

Before making connection to the power source, be sure the digitizing oscillo-scope has a suitable two-pole three-terminal grounding-type plug.

GROUNDING. This instrument is safety Class 1 equipment (IEC designation).All accessible conductive parts are directly connected through the groundingconductor of the power cord to the grounded (earthing) contact of the power plug.

The power input plug must be inserted only in a mating receptacle with agrounding contact where earth ground has been verified by a qualified serviceperson. Do not defeat the grounding connection. Any interruption of thegrounding connection can create an electric shock hazard.

For electric shock protection, the grounding connection must be made beforemaking connection to the oscilloscope input or output terminals.

A power cord with appropriate plug configuration is supplied with eachdigitizing oscilloscope. Table 2–1 gives the color coding of the conductors in thepower cord. If you require a power cord other than the one supplied, refer toTable 2–2.

Power Cord Information

Installation


Table 2–1: Power-Cord Conductor Identification

Conductor Color Alternate Color

Ungrounded (Line) Brown Black

Grounded (Neutral) Light Blue White

Grounded (Earthing) Green/Yellow Green

Table 2–2: Power Cord Identification

Plug Configuration Normal Usage Option Number

North America125 V

Standard

Europe230 V

A1

United Kingdom230 V

A2

Australia230 V

A3

North America230 V

A4

Switzerland230 V

A5

The line voltage ranges and their associated line frequency ranges over whichthis oscilloscope operates are listed in Chapter 1 Specification. See SourceVoltage and Frequency on page 1–18 for those ranges.

Operating Voltage

Installation


CAUTION. Before stepping the source line voltage from one range to a higherrange, set the principal power switch (rear panel) to its OFF position. Failure todo so can damage the oscilloscope.

There are two fuses. Either fuse may be used throughout the line voltage andfrequency ranges. These two fuses are not totally interchangeable as eachrequires a different fuse cap. The fuses and their caps are listed by part number inChapter 10, Mechanical Parts List.

Replaceable lithium batteries maintain internal memory modules to allow thedigitizing oscilloscope to retain the following data upon loss of the AC powersource: stored adjustment constants, saved front-panel settings, current front-pa-nel settings (oscilloscope status), and saved waveforms.

These batteries have a shelf life of about five years. Partial or total loss of storedsettings upon powering on may indicate that you need to replace the batteries.

Operating EnvironmentThe following environmental requirements are provided to ensure properoperation and long oscilloscope life.

Operate the oscilloscope where the ambient air temperature is between 0� C and+50� C, and store the oscilloscope at an ambient temperature from –40� C to+75� C. After storage at temperatures outside the operating limits, allow thechassis to stabilize at a safe operating temperature before applying power.

The digitizing oscilloscope is cooled by air drawn in and exhausted through itscabinet side panels by an internal fan. To ensure proper cooling of the oscillo-scope, allow at least 50.8 mm (2 inches) clearance on both sides and 19 mm(3�4 inch) on the bottom of the digitizing oscilloscope. (The feet on the bottom ofthe oscilloscope provide the required clearance when set on flat surfaces.) Thetop of the oscilloscope does not require ventilation clearance.

CAUTION. If air flow is restricted, the power supply of the digitizing oscilloscopemay temporarily shut down.

Memory Backup Power

Operating Temperature

Ventilation Requirements

Installation


Applying and Interrupting PowerConsider the following information when you power up or power down theoscilloscope or when power is interrupted due to an external power failure.

Upon powering on, the oscilloscope runs its power-on self check. If the selfcheck passes, the oscilloscope displays a “passed” status message and a promptto press CLEAR MENU to continue. If the self check fails, the oscilloscopedisplays a diagnostic log that identifies the area(s) that failed and a prompt topress CLEAR MENU to continue. See Chapter 6, Maintenance, for informationon diagnostics and fault isolation.

CAUTION. DO NOT power down the oscilloscope when either running a signalpath compensation or when doing any of the adjustments described in Chap-ter 5, Adjustment Procedures. To do so might result in the loss of internallystored adjustment constants.

In general, do not power off the oscilloscope when doing operations that affectthe data types listed in Table 2–3. Wait for the oscilloscope to finish theoperation when doing adjustments, saving waveforms, or saving setups. Afteroperations complete, wait at least four more seconds before turning the power off.

Improper power-down or unexpected loss of power to the oscilloscope can resultin corruption of non-volatile RAM (NVRAM). The following table describes themessages displayed when power is restored after an abnormal power-down.

Table 2–3: Effects of Corrupted Data

Corrupted Data Type Results

Adjustment Constants:

� Signal Path Compensation A signal path compensation is required.

� Voltage Reference A voltage reference adjustment is required(Chapter 5)

� Low or High Frequency Response A frequency response adjustment is required(Chapter 5)

� Trigger Skew A trigger skew adjustment is required(Chapter 5)

Error Log Errors logged are lost

Power-On

Power-Off

Installation


Table 2–3: Effects of Corrupted Data (Cont.)

Corrupted Data Type Results

Reference Waveforms Waveform Lost

Saved Setups Setup Lost

Repackaging InstructionsUse a corrugated cardboard shipping carton having a test strength of at least125 kg (275 pounds) and with an inside dimension at least 152.4 mm (6 inches)greater than the oscilloscope dimensions. (The original shipping carton, ifavailable, meets these requirements.)

If the oscilloscope is being shipped to a Tektronix Service Center, enclose thefollowing information: the owner’s address, the name and phone number of acontact person, the type and serial number of the oscilloscope, the reason forreturning to oscilloscope, and a complete description of the service required.

Seal the shipping carton with an industrial stapler or strapping tape.

Mark the address of the Tektronix Service Center and also your own returnaddress on the shipping carton in two prominent locations.

Installed OptionsYour oscilloscope may be equipped with one or more options. Except for theline-cord options described by Table 2–2 (on page 2–2 of this chapter), alloptions and optional accessories are listed and described in Chapter 7, Options.For further information and prices of oscilloscope options, see your TektronixProducts catalog or contact your Tektronix Field Office.

Installation



Operating Information

Before doing service, read the following operating instructions. These instruc-tions are at the level appropriate for servicing this digitizing oscilloscope. Thecomplete operators instructions are found in the user manual.

Additional instructions are integrated into the service procedures found in laterchapters of this manual. For instance, the procedures found in the PerformanceVerification chapter, starting on page 4–1, contain instructions for making thefront-panel settings required to check each oscilloscope characteristic includedthere. Also, the general instructions for operating the internal diagnostic routinesare found in the, Maintenance chapter, starting on page 6–1. You may also findthe Product Description, starting on page 1–1, useful for understanding how theoscilloscope functions.

Screen LayoutThe screen layout is illustrated in Figure 2–1 on page 2–8. Note that the figureillustrates a full graticule; you may also select a grid, crosshair, or framegraticule from the display menu.

Basic Procedures

Push the principal power switch found on the rear panel of the digitizingoscilloscope, then push the ON/STBY (standby) switch to toggle the digitizingoscilloscope into operation. The switch at the rear panel is the true powerdisconnect switch. The ON/STBY(standby) switch simply toggles operation onand off.

WARNING. The principal power switch at the rear panel is the true powerdisconnect switch. The ON/STBY (standby) switch simply toggles operation onand off. When connected to a power source and when the principal power switchis on, some power supply circuitry in this digitizing oscilloscope is energizedregardless of the setting of the ON/STBY switch.

When connecting or disconnecting the line cord to or from the power source, theprincipal power switch should be off.

How to Power On



Position of WaveformRecord Relative to

the Screen and Display

General PurposeKnob Readout

Waveform ReferenceSymbols: Ground Levelsand Waveform Sources

Graticule and Waveforms

Side menu area.Readouts formeasurementsmove here whenCLEAR MENUis pressed.

Main menu display area. Readouts in lower graticulearea move here when CLEAR MENU is pressed.

Vertical Scale, HorizontalScale, and Trigger Level

Readouts

Brief StatusInformation

Figure 2–1: Map of Display Functions

Push the HELP front-panel button to enter help mode. Front-panel knobs andbuttons now display information about their function when turned or pushed.Push HELP again to exit help mode.

To get help information on a menu item, display the menu desired (if you are inhelp mode, exit help first). Push HELP. Now the menu buttons displayinformation about their function when pushed.

Push the SHIFT button, and then press the STATUS front-panel button. Thenpress the STATUS main-menu button to display the status menu. The messagesreflect the state of the acquisition system, whether it is running or stopped (and ifit is stopped, why), as well as setup-related information.

Using Help

Using the Status Menu



You set most functions by either using one or two front-panel buttons or knobs,or by pushing a front-panel button to use a main menu, and then a side menu toset the function. The following steps illustrate both procedures.

1. Locate the block that contains the function to be set.

Special Controls Block: Accessesall functions except those in theremaining three control blocks.

Vertical Controls andInputs Block

Horizontal ControlsBlock

Trigger ControlsBlock

Setting Functions



2. Select the waveform source(s). Position, scale, and set trigger level forwaveform source(s) directly from the front-panel. (Note that parentheses-en-closed numbers appear within the following steps. Each number refers to thecontrol(s) labeled with the same number in the figure that precedes the step.)

1 2

5

6

4

8

7

3

a. Input waveforms into these channels (7). Example: CH 1.

b. Push any channel button (8) to display its waveform. The last channelselected determines which waveform is positioned and scaled. Theindicator above the channel last selected is lighted. Example: PushCH 1; then CH 2.

c. Vertically (1) and horizontally (2) scale and position the waveform(s)selected. Example: Set the scale to 100 mV/div, and center the waveformon screen.

d. Stop and start acquiring waveforms (3). Example: Push RUN/STOP ifnot acquiring.



e. Adjust trigger level (5) to trigger the waveform(s) selected, or use thesebuttons (6) to either set a trigger level at the mid-amplitude level of theselected waveform or to force a single trigger. Example: Push SETLEVEL TO 50% .

3. Set all other functions using menus.

a. Choose the waveform source (8) first if setting a vertical function; elseskip to step b. Example: Push CH 2.

b. Push SHIFT (4) if the function to be set is highlighted in blue; else skipto step c.

9

11

12

13

10

14

c. Push the front-panel button that corresponds to the menu containing thefunction. A main menu (14) for selecting among related functionsappears. Example: Push VERTICAL MENU .

Note the two labels: the top label is a function to choose from; thebottom label tells you the current setting for that function. Offset iscurrently set to –1.4 V.

d. Select a function from the main menu using the main menu buttons (12).A side menu for selecting among the available settings for that functionappears. Example: Push Coupling (13).



e. Select the setting for the function from the side menu (9) using the sidemenu buttons (11). Example: Push AC (10).

A few functions require more than just two levels (main and side) of menus tocompletely specify their settings. In such cases, either the main menu, the sidemenu, or both are modified to supply additional choices. The procedures thatfollow show both schemes.

1. Set up a function using pop-up menus:

18

17

15

16

a. For some selections, pushing a main menu button pops up a menu (18)of subfunctions. Example: Push SHIFT; then push UTILITY . Nowpush System (17).

Note the pop-up menu for System is set to I/O (input/output). All themain menu buttons to the right of the pop-up menu are labeled withsubfunctions of I/O .

b. Pushing the button that popped up the menu (17) toggles through thepop-up menu choices. Example: Repeatedly push System to togglethrough the pop-up menu. Notice the other main-menu button labelschange accordingly. Toggle back to I/O .

How to Set ComplexFunctions



c. Complete the setting of the desired mode by selecting from the mainmenu and the side menu that results. Example: Push Configure (16),and then push Hardcopy (Talk only) (15).

2. Set up a function using the general purpose knob (20). (The examples ofpossible menu selections in the substeps that follow assume you have pushedTRIGGER MENU .)

2019

21

a. Pushing some main menu buttons displays a side menu with labelscontaining readouts that you can vary. Example: Push Level (21).

b. Pushing the side-menu button assigns the knob to control the readoutappearing in the button label. It also copies the readout to the generalpurpose knob readout area in the right corner of the screen. Example:Push Level (19).

c. Use the general purpose knob (20) to adjust the trigger level to thesetting desired. Example: Turn the knob to –20 mV.



More About the General Purpose Knob. As you have just seen, the general purposeknob is used to extend the number of choices available to a side menu button.You can also assign the general purpose knob to control additional functions.Some of these additional functions include:

� Cursor positioning

� Display intensities

� Delay time

� Number of events

� Trigger position

� Holdoff

� Offset

� Variable persistence

� File system

In all cases, the menus are used to select the function to which the generalpurpose knob is assigned. The following attributes apply to this knob:

� Depending on the function it is assigned to control, the general purpose knobvaries numerical readouts, positions objects (cursors) on screen, or selectsbetween icon-label settings that show up in side-menu labels.

� The general purpose knob has a readout area at the upper-right corner of thescreen. (See Figure 2–1.) This readout always reflects the name and value ofthe function that the general purpose knob is currently controlling.

� The general purpose knob is affected by the SHIFT button. Pressing shifttoggles the knob between its fine and coarse modes. Fine mode is used formost adjustments; coarse mode is used to traverse large parts of theadjustment range in less time.

� Whenever the general purpose knob assignment is changed, a knob iconappears immediately to the left of the general purpose knob readout to notifyyou of the assignment change. The icon is removed as soon as you use thegeneral purpose knob to change the value of the function it is assigned to.

� To assign the general purpose knob to control a function, display the menucontaining the function; then select the function. (Note that the generalpurpose knob cannot control all functions.)



� Whenever the menu is removed, the general purpose knob is not assignedand does not control a function. (An exception is the cursor function. Ifcursors are turned on, removing the menu leaves the knob assigned tocontrol the cursors until reassigned by selecting another menu and functionthat uses the knob.)

� The general purpose knob also has a SELECT button. Use the select buttonto toggle the knob between the control of either of the two cursors displayedwhen H-bar or V-bar cursors are turned on in the cursor menu, to select theactive graticule in zoom preview, to traverse the file system, and to entercharacters when naming files.

Display and Utility Menus. Using the techniques described for using menus, youcan access and change functions in the display menu and utilities menu. In theDisplay menu, you can set the following functions:

� Intensity: waveforms, readouts, and graticule

� Style of waveform display(s): vectors or dots, intensified or non-intensifiedsamples, and infinite or variable persistence

� Display format: XY or YT

� Graticule format: full, grid, crosshair, frame, NTSC, and PAL

� Waveform interpolation filter and readout options

From the Utility menu, you can configure the GPIB port (talk/listen, address,etc.) and access internal routines for self diagnostics and self compensation.Instructions for setting up communication over the GPIB are found in theAdjustment Procedures, starting on page 5–1.




Theory of Operation

This chapter describes the electrical operation of the Tektronix TDS 420A,TDS 430A, and TDS 460A Digitizing Oscilloscopes using the major circuitblocks or modules.

This chapter has two main parts:

� Logic Conventions describes how logic functions are discused andrepresented in this manual.

� Module Overview describes circuit operation from a functional block perspective.

Logic ConventionsThe digitizing oscilloscope contains many digital logic circuits. This manualrefers to these circuits with standard logic symbols and terms. Unless otherwisestated, all logic functions are described using the positive-logic convention: themore positive of the two logic levels is the high (1) state, and the more negativelevel is the low (0) state. Signal states may also be described as “true” meaningtheir active state or “false” meaning their non-active state. The specific voltagesthat constitute a high or low state vary among the electronic devices.

Active-low signals are indicated by a tilde prefixed to the signal name (~RE-SET). Signal names are either active-high, active-low, or have both active-highand active-low states.

Module OverviewThis module overview describes the basic operation of each functional circuitblock as shown in Figure 9-2 on page 9–4.

The digitizing oscilloscope is a portable, multichannel instrument. Each channelprovides a calibrated vertical scale factor. All channels can be acquired simulta-neously.

A signal enters the oscilloscope through a probe connected to a BNC on theA05 Attenuator board.

Attenuators. Circuitry in the attenuator selects the input coupling, the termina-tion, and the attenuation factor. The processor system controls the attenuators.

General

Input Signal Path

Theory of Operation


For example, if 50� input termination is selected and the input is overloaded,the processor system switches the input to the 1 M� position. The preamplifierin the A05 Attenuator amplifies the input signals.

Probe Coding Interface. Probe coding interface signals pass through theA06 Front Panel to the processor system.

Jumper. Signals from the attenuators pass through the A08 Jumper board to theacquisition system.

Acquisition System. The acquisition system converts the analog input signals todigital signals and controls the acquisition process under direction of theprocessor system. The acquisition system includes the trigger, acquisition timing,and acquisition mode generation and control circuitry.

D1 Bus. The acquisition system passes the digital values representing theacquired waveform through the D1 bus to the A09 DSP board (TriStar). Thishappens after a waveform acquisition is complete if the digital signal processor(DSP) requests the waveform.

Processor System. The processor system consists of a 68020 microprocessor thatcontrols the entire instrument. It includes the firmware program for the oscillo-scope. The firmware can be reprogrammed by using the GPIB and an externalsoftware package. The processor system also includes a GPIB interface. Theprocessor can display text and symbols (that is, cursors, but not waveforms) bypassing them to the A02 Display board.

DSP. The digital signal processor processes each waveform as directed bysoftware downloaded from the system processor. Waveforms to be displayed arepassed on to the A02 Display board.

Display. Text and waveforms are processed by different parts of the A02 Displaycircuitry. The display sends the text and waveform information to the A26 Moni-tor assembly as a video signal. The display circuitry also generates and sendsvertical (VSYNC) and horizontal (HSYNC) sync signals to the A26 Monitorassembly. A VGA-compatible video output is available at the rear of theoscilloscope.

Theory of Operation


All information (waveforms, text, graticules, and pictographs) is displayed bythe A20 CRT Driver. The driver generates the high voltages necessary to drivethe CRT. It also contains the video amplifier, horizontal oscillator, and thevertical and horizontal yoke driver circuitry. The monitor gets its supply voltagesfrom the A25 Low Voltage Power Supply through the A01 Backplane and theA07 Auxiliary Power boards.

The processor system sends instructions to and receives information from theFront Panel Processor on the A06 Front Panel board. The Front Panel Processorreads the front-panel switches and pots. Any changes in their settings arereported to the processor system. The Front Panel Processor also turns the LEDson and off, generates the bell signal, and generates the probe compensationsignal PROBE ADJ. The Front Panel Processor also processes the probe codinginterface signals.

The ON/STBY switch is not read by the Front Panel Processor. The signalpasses through the A06 Front Panel board to the A03 CPU board. There it’sconverted to a control signal for the low voltage power supply.

The GPIB connector provides access to stored waveforms and allows externalcontrol of the oscilloscope. Other connectors accessible from the rear panel arethe AUX TRIGGER/EXT CLOCK and VIDEO.

The A07 Auxiliary Power circuitry includes the principal power switch, fuse,line trigger transformer, and line filter. It also distributes power to the monitorand fan.

The low voltage power supply is a switching power converter. It supplies powerto all oscilloscope circuitry. The low voltage power supply sends all of its powerto the A01 Backplane where it is distributed to all other circuitry.

The principal POWER switch, located on the rear panel, controls all power to theoscilloscope including the low voltage power supply. The ON/STBY switch,located on the front panel, also controls all of the power to the oscilloscopeexcept for part of the circuitry in the low voltage power supply.

The fan provides forced air cooling for the oscilloscope. It connects to +12 V onthe A01 Backplane through the A07 Auxiliary Power board.

The battery provides power to memory circuits that maintain calibrationconstants and oscilloscope setups when the oscilloscope power is off.

Monitor Assembly

Front Panel

Rear Panel

Aux Power

Low Voltage Power Supply

Fan

Battery

Theory of Operation



Performance Verification Procedures

Two types of Performance Verification procedures can be performed on thisproduct: Brief Procedures and Performance Tests. You may not need to performall of these procedures, depending on what you want to accomplish:

� To rapidly confirm that this oscilloscope functions and is adjusted properly,just do the procedures under Self Tests, which begin on page 4–5.

Advantages: These procedures are quick to do, require no externalequipment or signal sources, and perform extensive functional and accuracytesting to provide high confidence that the oscilloscope will performproperly. Use these procedures as a quick check before making a series ofimportant measurements.

� To further check functionality, first do the Self Tests just mentioned; then dothe procedures under Functional Tests that begin on page 4–7.

Advantages: These procedures require minimal additional time to perform,require no additional equipment other than a standard-accessory probe, andmore completely test the internal hardware of this oscilloscope. Use theseprocedures to quickly determine if the oscilloscope is suitable for puttinginto service, such as when it is first received.

� If more extensive confirmation of performance is desired, do the Perfor-mance Tests, beginning on page 4–15, after doing the Functional and SelfTests just referenced.

Advantages: These procedures add direct checking of warranted specifica-tions. They require more time to perform and suitable test equipment isrequired. (See Equipment Required on page 4–16.)

If you are not familiar with operating this oscilloscope, read Operating Informa-tion in Chapter 2 of this manual. These instructions will acquaint you with theuse of the front-panel controls and the menu system.

Throughout these procedures the following conventions apply:

� Each test procedure uses the following general format:

Title of Test

Equipment Required

Prerequisites

Procedure



� Each procedure consists of as many steps and substeps as required to do thetest. Steps and substeps are sequenced as follows:

1. First Step

a. First Substep

b. Second Substep

2. Second Step

� In steps and substeps, the lead-in statement in italics instructs you what todo, while the instructions that follow tell you how to do it: in the examplestep below, “Initialize the oscilloscope” by doing “Press save/recall SETUP.Now, press the main-menu button...”

Initialize the oscilloscope: Press save/recall SETUP. Now, press themain-menu button Recall Factory Setup; then the side-menu button OKConfirm Factory Init .

� Where instructed to use a front-panel button or knob, or select from a mainor side menu, or verify a readout or status message, the name of the button orknob appears in boldface type: “press SHIFT; then ACQUIRE MENU ,”“press the main-menu button Coupling,” or “verify that the status messageis Pass.”

STOP. This symbol is accompanied by information you must read to do procedures properly.

� Refer to Figure 4–1: “Main menu” refers to the menu that labels the sevenmenu buttons under the display; “side menu” refers to the menu that labelsthe five buttons to the right of the display.



Position of WaveformRecord Relative to

the Screen and Display

General PurposeKnob Readout

Waveform ReferenceSymbols: Ground Levelsand Waveform Sources

Graticule and Waveforms

Side menu area.Readouts formeasurementsmove here whenCLEAR MENUis pressed.

Main menu display area. Readouts in lower graticulearea move here when CLEAR MENU is pressed.

Vertical Scale, HorizontalScale, and Trigger Level

Readouts

Brief StatusInformation

Figure 4–1: Map of Display Functions




Brief Procedures

The Self Tests use internal routines to confirm basic functionality and properadjustment. No test equipment is required to do these test procedures.

The Functional Tests use the probe-adjust output at the front panel as a test-signal source for further verifying that the oscilloscope functions properly. Astandard-accessory probe, included with this oscilloscope, is the only equipment required.

Self TestsThis procedure uses internal routines to verify that this oscilloscope functionsand passes its internal self tests and signal path compensations. It also confirmsthat the oscilloscope was adjusted properly at the time it was last adjusted. Notest equipment or hookups are required.

EquipmentRequired

None

Prerequisites Power on the digitizing oscilloscope and allow a 20 minute warm-upbefore doing this procedure.

1. Verify that internal diagnostics pass: Do the following substeps to verify thatthe internal diagnostics passed.

a. Display the system diagnostics menu:

� Press SHIFT; then press UTILITY .

� Repeatedly press the main-menu button System until Diag/Err ishighlighted in the menu that pops up.

� Repeatedly press the main-menu button Area until All is highlightedin the menu that pops up.

b. Run the system diagnostics: Press the main-menu button Execute; thenpress the side-menu button OK Confirm Run Test.

c. Wait: The internal diagnostics do an exhaustive verification of properoscilloscope function. This verification takes up to two minutes. While itprogresses, a variety of test patterns flash on screen. When finished, theresulting status appears on the screen.

d. Confirm no failures are found: Verify that no failures are found andreported on screen.

Verify Internal Adjustment,Self Compensation, and

Diagnostics

Brief Procedures


e. Confirm the four adjustment sections have passed status:

� Press SHIFT; then press UTILITY .

� Press the main menu button System until Cal is highlighted in thepop-up menu.

� Verify that the word Pass appears in the main menu under thefollowing menu labels: Voltage Reference, High FrequencyResponse, Low Frequency Response, and Trigger Skew. (SeeFigure 4–2.)

Verify Pass status for theadjustment sections.

Run a signal pathcompensation and verify

status is Pass.

Display the CAL menu. 1

23

Figure 4–2: Verifying Adjustments and Signal Path Compensation

This oscilloscope lets you compensate the internal signal path used to acquire thewaveforms you acquire and measure. By executing the signal path compensationfeature (SPC), you optimize the oscilloscope capability to make accuratemeasurements based on the ambient temperature.

Brief Procedures


You must run an SPC anytime you wish to ensure that the measurements youmake are made with the most accuracy possible. You should also run an SPC ifthe temperature has changed more than 5� C since the last SPC was performed.

f. Run the signal path compensation: Disconnect all input signals. Pressthe main-menu button Signal Path; then press the side-menu button OKCompensate Signal Paths.

NOTE. Failure to run the signal path compensation may result in the oscilloscopenot meeting warranted performance levels.

g. Wait: signal path compensation runs in one to three minutes. While itprogresses, a “clock” icon (shown at left) displays on screen. Whencompensation completes, the status message updates to Pass or Fail inthe main menu (see step h).

h. Confirm signal path compensation returns passed status: Verify theword Pass appears under Signal Path in the main menu. (See Figure 4–2.)

2. Return to regular service: Press CLEAR MENU to exit the system menus.

Functional TestsThe purpose of these procedures is to confirm that this oscilloscope functionsproperly. The only equipment required is one of the standard-accessory probesand a 3.5�, 720 K or 1.44 Mbyte floppy disk.

Brief Procedures


STOP. These procedures verify functions; that is, they verify that oscilloscopefeatures operate. They do not verify that they operate within limits. Therefore,when the instructions in the functional tests that follow call for you to verify thata signal appears on screen “that is about five divisions in amplitude” or “has aperiod of about six horizontal divisions,” and so forth, do NOT interpret thequantities given as limits. Operation within limits is checked in PerformanceTests, which begin on page 4–15.

DO NOT make changes to the front-panel settings that are not called out in theprocedures. Each verification procedure requires you to set the oscilloscope tocertain default settings before verifying functions. If you make changes to thesesettings, other than those called out in the procedure, you may obtain invalidresults. In this case, just redo the procedure from step 1.

When you are instructed to press a menu button, the button may already beselected (its label will be highlighted). If this is the case, it is not necessary topress the button.

EquipmentRequired

One P6138A probe

Prerequisites None

1. Install the test hookup and preset the oscilloscope controls:

Digitizing Oscilloscope

Figure 4–3: Universal Test Hookup for Functional Tests

a. Hook up the signal source: Install the probe on CH 1. Connect the probetip to PROBE ADJ on the front panel; leave the probe ground unconnected.

Verify All Input Channels

Brief Procedures


b. Initialize the oscilloscope:

� Press save/recall SETUP.

� Press the main-menu button Recall Factory Setup.

� Press the side-menu button OK Confirm Factory Init .

2. Verify that all input channels operate: Do the following substeps — testCH 1 first, skipping substep a since CH 1 is already set up for verificationfrom step 1.

a. Select an unverified channel:

� Press WAVEFORM OFF to remove from display the channel just verified.

� Press the front-panel button that corresponds to the channel you areto verify.

� Move the probe to the channel you selected.

b. Set up the selected channel:

� Press AUTOSET to obtain a viewable, triggered display in theselected channel.

� Set the vertical SCALE to 100 mV. Use the vertical POSITIONknob to center the waveform vertically on screen.

� Set the horizontal SCALE to 200 �s.

� Press TRIGGER MENU .

� Press the main-menu button Coupling; then press the side menu-button HF Rej.

c. Verify that the channel is operational: Confirm that the followingstatements are true.

� The vertical scale readout for the channel under test shows a settingof 100 mV, and a square-wave probe-compensation signal about fivedivisions in amplitude is on screen. (See Figure 4–1 on page 4–3 tolocate the readout.)

� The vertical POSITION knob moves the signal up and down thescreen when rotated.

� Turning the vertical SCALE knob counterclockwise decreases theamplitude of the waveform on-screen, turning the knob clockwiseincreases the amplitude, and returning the knob to 100 mV returnsthe amplitude to about five divisions.

Brief Procedures


d. Verify that the channel acquires in all acquisition modes: Press SHIFT;then press ACQUIRE MENU . Use the side menu to select, in turn, eachof the five hardware acquire modes and confirm that the followingstatements are true. Refer to the icons at the left of each statement as youconfirm those statements.

� Sample mode displays an actively acquiring waveform on screen.(Note that there is noise present on the peaks of the square wave.)

� Peak Detect mode displays an actively acquiring waveform onscreen with the noise present in Sample mode “peak detected.”

� Hi Res mode displays an actively acquiring waveform on screenwith the noise that was present in Sample mode reduced.

� Envelope mode displays an actively acquiring waveform on screenwith the noise displayed.

� Average mode displays an actively acquiring waveform on screenwith the noise reduced like in Hi Res mode.

e. Test all channels: Repeat substeps a through d until all input channelsare verified.

3. Remove the test hookup: Disconnect the probe from the channel input andthe probe-adjust terminal.

EquipmentRequired

One P6138A probe

Prerequisites None


a. Hook up the signal source: Install the probe on CH 1. Connect the probetip to PROBE ADJ on the front panel; leave the probe ground uncon-nected. (See Figure 4–3 on page 4–8.)



� Press the main-menu button Recall Factory Setup; then press theside-menu button OK Confirm Factory Init .

c. Modify default settings:

� Press AUTOSET to obtain a viewable, triggered display.


Verify the Time Base

Brief Procedures


� Press VERTICAL MENU .

� Press the main-menu button Bandwidth. Then press the side-menubutton 20 MHz.

� Press CLEAR MENU to remove the vertical menu from the screen.

2. Verify that the time base operates: Confirm the following statements.

a. One period of the square-wave probe-compensation signal is about fivehorizontal divisions on-screen for the 200 �s horizontal scale setting (setin step 1c).

b. Rotating the horizontal SCALE knob clockwise expands the waveformon-screen (more horizontal divisions per waveform period), counter-clockwise rotation contracts it, and returning the horizontal scale to200 �s returns the period to about five divisions.

c. The horizontal POSITION knob positions the signal left and right onscreen when rotated.

3. Remove the test hookup: Disconnect the probe from the channel input andthe probe-adjust terminal.

EquipmentRequired

One P6138A probe

Prerequisites None


a. Hook up the signal source: Install the probe on CH 1. Connect the probetip to PROBE ADJ on the front panel; leave the probe ground uncon-nected. (See Figure 4–3 on page 4–8.)





c. Modify default settings:

� Press AUTOSET to obtain a viewable, triggered display.

� Set the horizontal SCALE for the M (main) time base to 200 �s.


Verify the Main andDelayed Trigger Systems

Brief Procedures


� Press the main-menu button Bandwidth; then press the side-menubutton 20 MHz.


� Press the main-menu button Mode & Holdoff .

� Press the side-menu button Normal.

� Press CLEAR MENU to remove the menus from the screen.

2. Verify that the main trigger system operates: Confirm that the followingstatements are true.

� The trigger-level readout for the main trigger system changes whenyou rotate the trigger MAIN LEVEL knob.

� The trigger-level knob can trigger and untrigger the square-wavesignal as you rotate it. (Leave the signal untriggered.)

� Pressing SET LEVEL TO 50% triggers the signal that you just leftuntriggered. (Leave the signal triggered.)

3. Verify that the delayed trigger system operates:

a. Select the delayed time base:

� Press HORIZONTAL MENU .

� Press the main-menu button Time Base.

� Press the side-menu button Delayed Triggerable; then press theside-menu button Delayed Only.

� Set the horizontal SCALE for the D (delayed) time base to 200 �s.

b. Select the delayed trigger-level menu:

� Press SHIFT; then press DELAYED TRIG .

� Press the main-menu button Level; then press the side-menu button Level.

c. Confirm that the following statements are true:

� The trigger-level readout for the delayed trigger system changeswhen you rotate the general purpose knob.

� The general purpose knob can trigger and untrigger the square-waveprobe-compensation signal as you rotate it. (Leave the signal untriggered.)

Brief Procedures


� Pressing the side-menu button Set to 50% triggers the probe-com-pensation signal that you just left untriggered. (Leave the signal triggered.)

d. Verify the delayed trigger counter:

� Press the main-menu button Delay by Time.

� Press the side-menu button Events, just below the Triggerable afterTime selection.

� Use the General Purpose knob to enter an event count of 325 events.

� Verify that the trigger READY indicator on the front panel flashesabout once every second as the waveform is updated on screen.

4. Remove the test hookup: Disconnect the standard-accessory probe from thechannel input and the probe-adjust terminal.

EquipmentRequired

One 720 K or 1.44 Mbyte, 3.5 inch DOS compatible disk (formatted).

Prerequisites None

1. Preset the digitizing oscilloscope controls:

a. Insert the disk in the disk drive.

b. Press save/recall SETUP. Press the main menu button Recall FactorySetup; then press the side menu button Ok Confirm Factory Init .

c. Set the horizontal SCALE to 200 �s (one click clockwise). Notice thehorizontal readout now displays 200 �s at the bottom of the screen.

2. Verify the file system works:

a. Press save/recall SETUP. Press the main menu button Save CurrentSetup; then press the side menu button To File.

b. Turn the general purpose knob to select the file to save. ChooseTEK?????.SET . With this choice, you will save a file starting with TEK,then containing five digits, and a .SET extension. For example, the firsttime you run this on a blank, formatted disk or on the Example ProgramsDisk, the digitizing oscilloscope will assign the name TEK00000.SET toyour file. If you ran the procedure again, the digitizing oscilloscopewould increment the name and call the file TEK00001.SET .

c. Press the side-menu button Save To Selected File.

Verify the File System

Brief Procedures

4–14REV DEC 93

TDS 420A, TDS 430A & TDS 460A Service Manual

d. Set the horizontal SCALE to 500 �s, and then use the vertical POSI-TION knob to place the channel 1 baseline trace two divisions abovecenter screen.

e. Press the main menu button Recall Saved Setup; then press the sidemenu button From File.

f. Turn the general purpose knob to select the file to recall. For example, ifyou followed the instructions above and used a blank disk, you had thedigitizing oscilloscope assign the name TEK00000.SET to your file.

g. Press the side-menu button Recall From Selected File.

h. Verify that the digitizing oscilloscope retrieved the saved setup from thedisk. Do this by noting that the horizontal SCALE again reads 200 �sand the channel 1 baseline waveform is again vertically positioned nearcenter screens as when you saved the setup.

3. Remove the test hookup: Remove the disk from the disk drive.


Performance Tests

This section contains procedures for checking that the TDS 400A DigitizingOscilloscopes perform as warranted.

The procedures are arranged in four logical groupings: Signal Acquisition SystemChecks, Time Base System Checks, Triggering System Checks, and Output PortsChecks. They check all the characteristics that are designated as checked inChapter 1, Specifications. (The characteristics that are checked appear inboldface type under Warranted Characteristics in Chapter 1.) You can use theform at the end of this section as a test record.

The procedures are arranged in four logical groupings: Signal Acquisition SystemChecks, Time Base System Checks, Triggering System Checks, and Output PortsChecks. They check all the characteristics that are designated as checked inChapter 1, Specifications. (The characteristics that are checked appear inboldface type under Warranted Characteristics in Chapter 1.) You can use theform at the end of this section as a test record.

Read Performance Verification Procedures that start on page 4–1. Also, if youare not familiar with operating this digitizing oscilloscope, read OperatingInformation in Chapter 2 of the service manual or read the user manual beforedoing any of these procedures.

STOP. These procedures extend the confidence level provided by the basicprocedures described on page 4–5. The basic procedures should be done first,and then these procedures performed if desired.

PrerequisitesThe tests in this chapter comprise an extensive, valid confirmation of perfor-mance and functionality when the following requirements are met:

� The cabinet must be installed on the digitizing oscilloscope.

� You must have performed and passed the procedures under Self Tests, foundon page 4–5, and those under Functional Tests, found on page 4–7.

� A signal-path compensation must have been done within the recommendedcalibration interval and at a temperature within �5� C of the presentoperating temperature. (If at the time you did the prerequisite Self Tests, thetemperature was within the limits just stated, consider this prerequisite met.)

Performance Tests


� The digitizing oscilloscope must have been last adjusted at an ambienttemperature between +20� C and +30� C, must have been operating for awarm-up period of at least 20 minutes, and must be operating at an ambienttemperature between 5� C and +40� C. (The warm-up requirement is usuallymet in the course of meeting the prerequisites listed above.)

Equipment RequiredThese procedures use external, traceable signal sources to directly checkwarranted characteristics. The test equipment required is shown in Table 4–1.

Table 4–1: Test Equipment

Item Number and Description Minimum Requirements Example Purpose

1. Attenuator,10X (three required)

Ratio: 10X; impedance 50 �; connec-tors: female BNC input, male BNCoutput

Tektronix part number011-0059-02

Signal Attenuation

2. Attenuator, 5X (two required)

Ratio: 5X; impedance 50 �; connec-tors: female BNC input, male BNCoutput


Signal Attenuation

3. Termination, 50 � Impedance 50 �; connectors: femaleBNC input, male BNC output


Checking delay match be-tween channels

4. Termination, 75 � Impedance 75 �; connectors: femaleBNC input, male BNC output


Used to test Video Option 05equipped oscilloscopes only

5. Cable, Precision Coaxial(three required)

50 �, 36 in, male to male BNCconnectors


Signal Interconnection

6. Cable, Coaxial 75 �, 36 in, male to male BNCconnectors


Used to test Video Option 05equipped oscilloscopes only

7. Connector, Dual-Banana(two required)

Female BNC to dual banana Tektronix part number103-0090-00

Various Accuracy Tests

8. Connector, BNC “T” Male BNC to dual female BNC Tektronix part number103-0030-00

Checking Trigger Sensitivity

9. Coupler, Dual-Input Female BNC to dual male BNC Tektronix part number067-0525-02

Checking Delay Match Be-tween Channels

10. Generator, DC Calibra-tion

Variable amplitude to ±110 V; accura-cy to 0.1%

Wavetek 9100 (or, optionally,Data Precision 8200, with1 kV option installed)

Checking DC Offset andMeasurement Accuracy

11. Generator, Sine Wave 100 kHz to at least 400 MHz. Variableamplitude from 12 mV to 2 Vp-p.Frequency accuracy >2.0%

Rohde & Schwarz SMY1 Checking Analog Bandwidth,Trigger Sensitivity, Sample-rate, External Clock, andDelay-Time Accuracy

12. Meter, Level and PowerSensor

Frequency range:10 MHz to 400MHz.Amplitude range: 6 mVp-p to 2 Vp-p

Rohde & Schwarz URV 35,with NRV-Z8 power sensor

Checking Analog Bandwidthand Trigger Sensitivity

Performance Tests


Table 4–1: Test Equipment (Cont.)

Item Number and Description PurposeExampleMinimum Requirements

13. Splitter, Power Frequency range: DC to 1 GHz.Tracking: >2.0%

Rohde & Schwarz RVZ Checking Analog Bandwidth

14. Generator, Function Frequency range 5 MHz to 10 MHz.Square wave transition time �25 ns.Amplitude range: 0 to 10 Vp-p into 50�

Tektronix CFG280 Checking External Clock

15. Adapter (four required) Male N to female BNC Tektronix 103–0045–00 Checking Analog Bandwidth

16. Adapter Female N to male BNC Tektronix 103–0058–00 Checking Analog Bandwidth

17. Probe, 10X included withthis oscilloscope

A P6138A probe Tektronix P6138A Signal Interconnection

18. Generator, Video Signal Provides NTSC compatible outputs Tektronix TSG 1001 Checking Video Trigger Sensitivity

1 If available, items 11, 12, 13, and 15 can be replaced by a Tektronix SG 503 and SG 504. If available, a TG 501A may beused to check Sample-rate and Delay-time Accuracy. (A TM 500 or TM 5000 Series Power Module Mainframe is required.)If using a TG 501A, you may also need a 2X attenuator (50 � BNC), Tektronix part number 011-0069-02.

Performance Tests


Test RecordPhotocopy this page and the next page and use them to record the performancetest results for your oscilloscope.

TDS 400A Test Record

Oscilloscope Serial Number: Certificate Number:Temperature: RH %:Date of Calibration: Technician:

Performance Test Minimum Incoming Outgoing Maximum

Offset Accuracy

CH1 Offset +1 V+10 V+99.9 V

995 mV9.935 V99.2505 V

______________________________

______________________________

+ 1.005 V+ 10.065 V+ 100.5495 V

CH2 Offset +1 V+10 V+99.9 V

995 mV9.935 V99.2505 V

______________________________

______________________________

+ 1.005 V+ 10.065 V+ 100.5495 V

CH3 Offset +1 V(TDS 420A & +10 VTDS 460A) +99.9 V

995 mV9.935 V99.2505 V

______________________________

______________________________

+ 1.005 V+ 10.065 V+ 100.5495 V

CH4 Offset +1 V(TDS 420A & +10 VTDS 460A) +99.9 V

995 mV9.935 V99.2505 V

______________________________

______________________________

+ 1.005 V+ 10.065 V+ 100.5495 V

DC Voltage Measurement Accuracy (Averaged)

CH1 100 mV –20.8 mV __________ __________ +20.8 mV

CH2 100 mV –20.8 mV __________ __________ +20.8 mV

CH3 100 mV (TDS 420A and TDS 460A) –20.8 mV __________ __________ +20.8 mV

CH4 100 mV (TDS 420A and TDS 460A) –20.8 mV __________ __________ +20.8 mV

Analog Bandwidth

CH1 100 mV 424 mV __________ __________ N/A

CH2 100 mV 424 mV __________ __________ N/A

CH3 100 mV (TDS 420A and TDS 460A) 424 mV __________ __________ N/A

CH4 100 mV (TDS 420A and TDS 460A) 424 mV __________ __________ N/A

Time Base System

Delay Between Channels N/A __________ __________ 450 ps

Delta Time @ 20 ns (100 MHz) 9.7 ns __________ __________ 10.3 ns

Long Term Sample Rate/Delay Time @ 10 ns/100 �s –1.5 Div __________ __________ +1.5 Div

Performance Tests


TDS 400A Test Record (Cont.)

Oscilloscope Serial Number: Certificate Number:Temperature: RH %:Date of Calibration: Technician:

Performance Test MaximumOutgoingIncomingMinimum

Trigger System (DC Coupled Threshold)

Main TriggerMain Trigger — Falling

–18 mV–18 mV

____________________

____________________

+18 mV+18 mV

Main TriggerDelayed Trigger — Falling

–18 mV–18 mV

____________________

____________________

+18 mV+18 mV

Auxiliary Trigger __________ __________ 10 MHz

External Clock __________ __________ 10 MHz

Probe Compensator Output Signal

Frequency 950 Hz __________ __________ 1050 Hz

Voltage 475 mV __________ __________ 525 mV

Performance Tests


Signal Acquisition System ChecksThese procedures check those characteristics that relate to the signal-acquisitionsystem and are listed as checked under Warranted Characteristics in Chapter 1,Specification.

EquipmentRequired

Two dual-banana connectors (Item 7)

One BNC T connector (Item 8)

One DC calibration generator (Item 10)

Two precision coaxial cables (Item 5)

Prerequisites See page 4–15.

1. Install the test hookup and preset the instrument controls:

a. Hook up the test-signal source:

� Set the output of a DC calibration generator to 0 volts.

� Connect the output of a DC calibration generator through adual-banana connector followed by a 50 � precision coaxial cable toone side of a BNC T connector (see Figure 4–4).

� Connect the Sense output of the generator through a seconddual-banana connector followed by a 50 � precision coaxial cable tothe other side of the BNC T connector. Now connect the BNC Tconnector to CH 1.


DC Calibrator

50 � Coaxial Cables

Dual Banana toBNC Adapters

BNC TConnector

Output Sense

Figure 4–4: Initial Test Hookup

Check Offset Accuracy

Performance Tests






c. Modify the default settings:

� Set the horizontal SCALE to 1 ms.

� Press SHIFT; then ACQUIRE MENU .

� Press the main-menu button Mode; then press the side-menu button Hi Res.

� Press DISPLAY.

� Press the main-menu button Graticule; then press the side-menubutton Frame.

� Press MEASURE.

� Press the main-menu button Select Measurement for CHx; thenpress the side-menu button Mean. (You will have to press MOREseveral times to access the Mean measurement.)

� Press CLEAR MENU .

2. Confirm input channels are within limits for offset accuracy: Do thefollowing substeps — test CH 1 first, skipping substep a since CH 1 isalready set up to be checked from step 1.

WARNING. High voltages are used in this procedure. Before doing this or anyother procedure in this manual, read the Safety Summary found at the beginningof this manual.

a. Select an unchecked channel:

� Press WAVEFORM OFF to remove the channel just confirmedfrom the display. Then, press the front-panel button that correspondsto the channel you are to confirm.

� Press MEASURE.


Performance Tests


Table 4–2: DC Offset Accuracy

Vertical Scale Setting

Vertical Position Offset Setting

Generator Setting

Offset Accuracy Limits

1 mV 0 +1 V +1 V ±5 mV

100 mV 0 +10 V +10 V ±65 mV

1 V 0 +99.9 V +99.9 V ±649.5 mV

b. Set the vertical scale: Set the vertical SCALE to one of the settingslisted in Table 4–2 that is not yet checked. (Start with the first setting listed.)

c. Set the offset: Press the VERTICAL MENU button and then the Offsetmain-menu button. Using the General Purpose knob, set the offset asdictated by Table 4–2. (Start with the first setting listed.)

d. Set the generator: Set the DC calibration generator to match the verticalscale as dictated by Table 4–2. (Start with the first setting listed.)

e. Check against limits: Do the following subparts in the order listed.

� Subtract the measured mean from the generator setting. The result isthe offset accuracy

� CHECK that the offset accuracy is within the limits listed for thecurrent vertical scale setting.

� Repeat substeps b through e until all vertical scale settings listed inTable 4–2 are checked for the channel under test.

f. Test all channels: Repeat substeps a through e for all input channels.

3. Disconnect the hookup:

a. Set the generator output to 0 V.

b. Then disconnect the cable from the generator output at the inputconnector of the channel last tested.

EquipmentRequired

Two dual-banana connectors (Item 7)





Check DC VoltageMeasurement Accuracy

(Averaged)

Performance Tests





� Connect the output of a DC calibration generator through adual-banana connector followed by a 50 � precision coaxial cable toone side of a BNC T connector (see Figure 4–5).

� Connect the Sense output of the generator through a seconddual-banana connector followed by a 50 � precision coaxial cable tothe other side of the BNC T connector. Now connect the BNC Tconnector to CH 1.


DC Calibrator



BNC TConnector

Output Sense







� Press SHIFT and then ACQUIRE MENU .

� Press the main-menu button Mode; then press the side-menu buttonAverage 16.

� Press DISPLAY.

� Press the main-menu button Graticule; then press the side-menubutton Frame.

Performance Tests


� Press MEASURE.


� Set the vertical SCALE to 100 mV.

� Press the VERTICAL MENU button and then the Offset main-menu button. Set the offset to 0 V.

� Set the vertical POSITION to 0 V.

2. Confirm input channels are within limits for DC delta voltage accuracy: Dothe following substeps — test CH 1 first, skipping substep a since CH 1 isalready selected from step 1.


� Set the generator output to 0 V.

� Press WAVEFORM OFF to remove the channel just confirmedfrom the display.

� Press the front-panel button that corresponds to the next channel youare to confirm.

� Press MEASURE.


� Move the test hook up to the channel you select.


� Set the vertical POSITION to 0 V.

� Press the VERTICAL MENU button and then the Offset main-menu button. Set the offset to 0 V.

b. Set the generator: Set the DC calibration generator to +0.35 V.

c. Record Measurement: Read the mean at the measurement readout, andrecord this number on a piece of scratch paper.

d. Set the generator: Set the DC calibration generator to –0.35 V.

Performance Tests


e. Check against limits: Do the following subparts in the order listed.

� Use this formula to calculate voltage measurement accuracy.

700 mV – (mean from step c – (present mean))

For example:

700 mV – (347 mV – (–358 mV)) = –5 mV

� CHECK that the voltage measurement accuracy is within �20.8 mV.

f. Test all channels: Repeat substeps a through e for all channels.


a. Set the generator output to 0 V.

b. Then disconnect the cable from the generator output at the inputconnector of the channel last tested.

EquipmentRequired

One sine wave generator (Item 11)

One level meter and power sensor (Item 12)

One power splitter (Item 13)

One Female N to Male BNC Adapter (Item 16)

Four Male N to Female BNC Adapters (Item 15)

Two 50 � precision cables (Item 5)

Two 10X attenuators (Item 1).



a. Initialize the oscilloscope:

� Press save/recall SETUP. Then press the main-menu button RecallFactory Setup.


b. Modify the default settings:


� Press the main-menu button COUPLING ; then press the side menubutton Noise Rej.

Check Analog Bandwidth

Performance Tests


� Press SHIFT; then ACQUIRE MENU .

� Press the main-menu button Mode; then press the side-menu buttonAverage 16.

� Press Measure. Now press the main-menu button High–Low Setup;then press the side-menu button Min–Max .

Digitizing OscilloscopeSine WaveGenerator

Output


NOTE. Refer to the Sine Wave Generator Leveling Procedure on page 4–55 ifyour sine wave generator does not have automatic output amplitude leveling.

c. Hook up the test-signal source:

� Connect the sine wave output of a sine wave generator to CH 1 (seeFigure 4–6). Set the output of the generator to a reference frequencyof 10 MHz or less.

� Set the horizontal SCALE to 50 ns. (If using a reference other than10 MHz, adjust the horizontal SCALE to display 4 to 6 cycles of the waveform.)

2. Confirm the input channels are within limits for analog bandwidth: Do thefollowing substeps — test CH 1 first, skipping substeps a and b since CH 1is already set up for testing from step 1.


� Press WAVEFORM OFF to remove the channel just confirmedfrom display.

� Press the front-panel button that corresponds to the channel you areto confirm.

� Move the leveled output of the sine wave generator to the channelyou select.

Performance Tests


b. Match the trigger source to the channel selected:


� Press the main-menu button Source.

� Press the side-menu button that corresponds to the channel selected.

c. Set the input impedance of the channel:

� Press VERTICAL MENU ; then press the main-menu button Coupling.

� Press the side-menu button � to toggle it to the 50 � setting.

d. Set the vertical scale: Set the vertical SCALE to one of the settingslisted in Table 4–3 (TDS 420A) or Table 4–4 (TDS 430A andTDS 460A) not yet checked. (Start with the 100 mV setting.)

Table 4–3: Analog Bandwidth (TDS 420A)

Vertical Scale Reference Amplitude Horizontal Scale Test Frequency Limits

100 mV 600 mV (6 divisions) 5 ns 200 MHz ≥424 mV

1 V1 2 V (2 divisions) 5 ns 200 MHz ≥1.414 V

500 mV 2 V (4 divisions) 5 ns 200 MHz ≥1.414 V

200 mV 1.2 V (6 divisions) 5 ns 200 MHz ≥848 mV





2 mV 12 mV (6 divisions) 5 ns 150 MHz ≥8.4 mV

1 mV 6 mV (6 divisions) 5 ns 95 MHz ≥4.2 mV1 If the oscilloscope does not trigger in step 2e, change the trigger coupling to DC for this Vertical Scale setting.

Performance Tests


Table 4–4: Analog Bandwidth (TDS 430A and TDS 460A)

Vertical Scale Reference Amplitude Horizontal Scale Test Frequency Limits


1 V1 2 V (2 divisions) 2 ns 400 MHz ≥1.414 V

500 mV 2 V (4 divisions) 2 ns 400 MHz ≥1.414 V

200 mV 1.2 V (6 divisions) 2 ns 400 MHz ≥848 mV





2 mV 12 mV (6 divisions) 2 ns 250 MHz ≥8.4 mV

1 mV 6 mV (6 divisions) 2 ns 100 MHz ≥4.2 mV1 If the oscilloscope does not trigger in step 2e, change the trigger coupling to DC for this Vertical Scale setting.

e. Display the test signal: Do the following subparts to first display thereference signal and then the test signal.

� Press MEASURE; then press the main-menu button SelectMeasurement for CHx.

� Now press the side menu button more until the menu label Pk-Pkappears in the side menu (its icon is shown at the left). Press theside-menu button Pk-Pk.


� Set the sine wave generator output (if necessary, use 10X attenua-tors) so the CHx Pk-Pk readout equals the reference amplitude inTable 4–3 (TDS 420A) or Table 4–4 (TDS 430A and TDS 460A)that corresponds to the vertical scale set in substep d.

� Press the front-panel button SET LEVEL TO 50% as necessary totrigger a stable display.

f. Measure the test signal:

� Increase the frequency of the generator output (leveled output) to thetest frequency in Table 4–3 (TDS 420A) or Table 4–4 (TDS 430Aand TDS 460A) that corresponds to the vertical scale set insubstep d.

� Set the horizontal SCALE to 5 ns (TDS 420A) or 2 ns (TDS 430Aand TDS 460A).

� Press SET LEVEL TO 50% as necessary to trigger the display.

Performance Tests


� Read the results at the CHx Pk-Pk readout, which automaticallymeasures the amplitude of the test signal. (See Figure 4–7.)

Set the horizontalscale from the tables.

Set the generatorfrequency to the test

frequency fromtables 4–3 and 4–4.

Read the resultsfrom the readout of

measurement Pk-Pk.

1

2

3

Figure 4–7: Measurement of Analog Bandwidth

g. Check against limits:

� CHECK that the Pk-Pk readout on screen is within the limits listedin Table 4–3 (TDS 420A) or Table 4–4 (TDS 430A andTDS 460A) for the current vertical scale setting.

� When finished checking, set the horizontal SCALE back to the50 ns setting (the setting you used in step 1b.

STOP. Checking the bandwidth of each channel at all vertical scale settings istime consuming and unnecessary. You may skip checking the remaining verticalscale settings in Table 4–3 (TDS 420A) or Table 4–4 (TDS 430A and TDS 460A)(that is, skip the following substep, h) if this digitizing oscilloscope has passedthe 100 mV vertical scale setting just checked in this procedure and passed theVerify Internal Adjustment, Self Compensation, and Diagnostics procedure foundunder Self Tests, on page 4–5.

Performance Tests


NOTE. Passing the signal path compensation confirms the signal path for allvertical scale settings for all channels. Passing the internal diagnostics ensuresthat the factory-set adjustment constants that control the bandwidth for eachvertical scale setting have not changed.

h. Check remaining vertical scale settings against limits (optional):

� If desired, finish checking the remaining vertical scale settings forthe channel under test by repeating substeps d through g for each ofthe remaining scale settings listed in Table 4–3 (TDS 420A) or Table4–4 (TDS 430A and TDS 460A) for the channel under test.

� When doing substep e, skip the subparts that turn on the CHx Pk-Pkmeasurement until you check a new channel.

� Install/remove 10X attenuators between the generator leveled outputand the channel input as is needed to obtain the six divisionreference signals listed in the tables.

i. Test all channels: Repeat substeps a through g for all channels.

3. Disconnect the hookup: Disconnect the test hook up from the inputconnector of the channel last tested.

EquipmentRequired


One precision coaxial cable (Item 5)

One 50 � terminator (Item 3)

One dual-input coupler (Item 9)


STOP. DO NOT use the vertical position knob to reposition any channel whiledoing this check. To do so invalidates the test.


a. Initialize the front panel:




Check Delay MatchBetween Channels

Performance Tests


b. Modify the initialized front-panel control settings:

� Do not adjust the vertical position of any channel during this procedure.

� Set the horizontal SCALE to 1 ns.

� Press SHIFT; then press ACQUIRE MENU .

� Press the main-menu button Mode, and then press the side-menubutton Average 16.


� Connect the sine wave output of a sine wave generator to a 50 �

precision coaxial cable, a 50 � termination, and a dual-inputcoupler. (See Figure 4–8.)

� Connect the coupler to both CH 1 and CH 2. Ensure that thecoupler cables are of equal length.


Dual InputCoupler

50 � Terminator

Output


2. Confirm all channels are within limits for channel delay:

a. Set up the generator: Set the generator frequency to 250 MHz and theamplitude for about five divisions in CH 1.

Hint: as you are adjusting the generator amplitude, push SET LEVELTO 50% frequently to speed up the updating of the waveform amplitudeon screen.

b. Save a CH 2 waveform: Press CH 2; then press save/recall WAVE-FORM . Now, press the main-menu button Save Waveform; then pressthe side-menu button To Ref 2.

Performance Tests


c. If you are testing a TDS 430A, skip to step h.

d. Save a CH 3 waveform: Move the coupler from CH 2 to CH 3, so thatCH 1 and CH 3 are driven. Press CH 3; then press the side-menu buttonTo Ref 3.

e. Display all test signals:

� Press WAVEFORM OFF twice to remove CH 2 and CH 3 from the display.

� Move the coupler from CH 3 to CH 4, so that CH 1 and CH 4 aredriven. Press CH 4 to display.

� Now, press the front-panel button MORE . Press the main-menubuttons Ref 2 and Ref 3.

f. Measure the test signal:

� Locate the point on the rising edge of the left-most waveform whereit crosses the center horizontal graticule line. This is the timereference point for this waveform. Note the corresponding timereference point for the right-most waveform. See Figure 4–9.

� Press CURSOR; then press the side-menu button V Bars.


� Rotate the General Purpose knob to align one cursor to the timereference point of the left-most waveform edge and the other cursorto the time reference point of the right-most waveform edge. (PressSELECT to switch between the two cursors.) See Figure 4–9.

� Read the measurement results at the �: cursor readout, not the @:readout on screen.

g. Check all channels against limit: CHECK that the cursor readout onscreen is ≤450 ps. If the cursor readout is ≤200 ps, skip substep h.

Performance Tests


Display the live/referencewaveforms for all four channels

Note their overlapping groundreferences.

Read theresults here.

Identify the time referencepoints of the waveforms.

Turn on the cursor and alignthe V bar cursors to the time

reference points.

1

2

3

4

Figure 4–9: Measurement of Channel Delay

h. Check CH 1 to CH 2 and CH 3 to CH 4 against limit:

� Press WAVEFORM OFF four times to remove all waveforms.

� Press CH 1.

� Press MORE ; then press the main-menu button Ref 2.

� Measure the delay between CH 1 and Ref 2 using the methoddescribed in substep f above.

� CHECK that the cursor readout on screen is ≤200 ps.

� If you are testing a TDS 430A, skip to step 3.

� Press WAVEFORM OFF twice to turn off CH 1 and Ref 2; thenpress CH 4 to turn on CH 4.

� Press MORE ; then press the main-menu button Ref 3 to display theCH 3 waveform stored in Ref 3.

� Measure the delay between Ref 3 and CH 4 using the methoddescribed in substep f above.

� CHECK that the cursor readout on screen is ≤200 ps.

Performance Tests


3. Disconnect the hookup: Disconnect the cable from the generator output atthe input connectors of the channels.

Time Base System ChecksThese procedures check those characteristics that relate to the Main and Delayedtime base system and are listed as checked under Warranted Characteristics inChapter 1, Specification.

EquipmentRequired

One time standard, either a frequency accurate sine wave generator ortime marker generator (Item 11)

Attenuators, 10X and 5X (Items 1 and 2)

One precision coaxial cable (Item 5).



a. Hook up the test-signal source: Connect, through a 50 � precisioncoaxial cable, the output of a time standard to CH 1 (see Figure 4–10).Set the output of the standard to 100 MHz (or a period of 10 ns).

TimeStandard


50 � Coaxial Cable

Output

Attenuator (if necessary)






Check Accuracy forLong-Term Sample Rate,

Delay Time, and DeltaTime Measurements

Performance Tests


c. Modify the initialized front-panel control settings:

� Press VERTICAL MENU ; then press the main-menu buttonCoupling. Press the side-menu button � to change the couplingsetting to 50 �.

� If necessary, set the vertical SCALE to 100 mV per division.

� Set the horizontal SCALE of the Main time base to 2.0 ns.

� Using external attenuators if necessary, adjust the time standardamplitude for a 5 to 7 division display.

� Rotate the vertical POSITION control to center the displayed waveform.

2. Confirm Main and Delayed time bases are within limits for accuracies:

a. Check delta-time accuracy against limits:

� Press SET LEVEL TO 50% .

� Press SHIFT; then ACQUIRE MENU . Now press the main-menubutton Mode; then press the side-menu button Average.

� Use the General Purpose knob to set the number of averages to 8.

� Press MEASURE.

� Press the main-menu button High-Low Setup; then press theside-menu button Min-Max .

� Press the main-menu button Select Measurement for Ch1.

� Press the side-menu button –more–, until PERIOD appears in theside menu. Press PERIOD.


� CHECK that the readout for CH 1 Per is within 9.7 ns to 10.3 ns.

b. Check long-term sample rate and delay time accuracies against limits:

� Press SHIFT; then ACQUIRE MENU . Now press the main-menubutton Mode; then press the side-menu button Sample.

� Press MEASURE.

� Press the main-menu button Remove Measurement; then press theside-menu button Measurement 1.

� Set the horizontal SCALE of the Main time base to 100 ns.

Performance Tests


� Set the frequency of the time standard to 1.0 MHz (or a period of1.00 �s).

� Adjust the amplitude of the time standard for a 5 to 7 division display.



� Rotate the horizontal and vertical POSITION controls to move therising edge of the waveform so that it crosses the center of both thehorizontal and vertical graticule lines.

� Press HORIZONTAL MENU ; then press the main-menu buttonTime Base. Press the side-menu button Delayed Only

� Use the horizontal SCALE knob to set the D (delayed) time base to 100 ns.

� Press the side-menu button Delayed Runs After Main; then use theGeneral Purpose knob to set Delayed Runs After Main to 10.0 �s.

� CHECK that the rising edge of the waveform crosses the centerhorizontal graticule line at a point within ±0.5 divisions of the centergraticule (see Figure 4–11).

� Use the horizontal SCALE knob to set the D (delayed) time base to 50 �s. (The scale of the Main time base will also change.)

� Use the General Purpose knob to set Delayed Runs After Mainto 100 �s.


� CHECK that the rising edge of the waveform crosses the centerhorizontal graticule line at a point within ±0.5 divisions of the center graticule.

Performance Tests


Check that the waveform risingedge is within ±0.5 horizontal

divisions on the centerhorizontal graticule line.

Enter a 10.0 �s delay and set the horizontalscale for the D time base to 100 ns.

Set thedelayedhorizontalmodes.

1

2

3

Figure 4–11: Measurement of Accuracy — Long-Term and Delay-Time

� Set the horizontal SCALE of the D (delayed) time base to 500 �s.(The scale of the Main time base will also change.)

� Use the General Purpose knob to set Delayed Runs After Mainto 1.00 ms.


� CHECK that the rising edge of the waveform crosses the centerhorizontal graticule line at a point within ±1.5 divisions of the center graticule.

3. Disconnect the hookup: Disconnect the cable from the time standard at theinput connector of CH 1.

Performance Tests


Trigger System ChecksThese procedures check those characteristics that relate to the Main and Delayedtrigger systems and are listed as checked under Warranted Characteristics inChapter 1, Specification.

EquipmentRequired








� Connect the output of a DC calibration generator through adual-banana connector followed by a 50 � precision coaxial cable toone side of a BNC T connector.

� Connect the Sense output of the generator, through a seconddual-banana connector followed by a 50 � precision coaxial cable,to the other side of the BNC T connector. Now connect the BNC Tconnector to CH 1 (see Figure 4–12).


DC Calibrator



BNC TConnector

Output Sense



� Press save/recall Setup.

Check Accuracy, TriggerLevel or Threshold, DC

Coupled

Performance Tests




2. Confirm Main trigger system is within limits for Trigger-level/Thresholdaccuracy:

a. Display the test signal:


� Set the standard output of a DC calibration generator to +0.3 V.

b. Measure the test signal:



� Read the measurement results from the readout below the labelLevel in the menu rather than from the trigger readout in thegraticule area.

c. Check against limits:

� Subtract the trigger level readout from the DC calibration generatorsetting. The result is the trigger level accuracy.

� CHECK that the trigger level is accurate to within �18 mV.

� Press TRIGGER MENU . Press the main-menu button Slope; thenpress the side-menu button for negative slope. (See icon at left.)Repeat substep b.



3. Confirm Delayed trigger system is within limits for Trigger-level/Thresholdaccuracy:

a. Select the Delayed time base:


� Press the main-menu button Time Base.

� Press the side-menu buttons Delayed Only and Delayed Triggerable.

� Set D (delayed) horizontal SCALE to 500 �s.

Performance Tests


b. Select the Delayed trigger system:

� Press SHIFT; then press the front-panel button DELAYED TRIG .

� Press the main-menu button Level.

c. Measure the test signal: Press the side-menu button SET TO 50%.Read the measurement results in the side menu below the label Level.

d. Check against limits: Do the following subparts in the order listed.



� Press TRIGGER MENU . Press the main-menu button Slope; thenpress the side-menu button for negative slope. (See icon at left.)




a. First set the output of the DC calibration generator to 0 volts.

b. Then disconnect the cable from the generator output at the inputconnector of CH 1.

EquipmentRequired


One precision 50� coaxial cable (Item 5)

One 10X attenuator (Item 1)








Sensitivity, Edge Trigger,DC Coupled

Performance Tests



� Set the horizontal SCALE for the M (main) time base to 20 ns.

� Press HORIZONTAL MENU ; then press the main-menu buttonTime Base.

� Press the side-menu button Delayed Only; then press the side-menubutton Delayed Triggerable.

� Set the horizontal SCALE for the D (delayed) time base to 20 ns;then press the side-menu button Main Only.

� Press TRIGGER MENU ; then press the main-menu button Mode& Holdoff . Now press the side-menu button Normal.

� Press VERTICAL MENU ; then press the main-menu buttonCoupling. Now press the side-menu button � to select the 50 � setting.

� Press SHIFT; then press ACQUIRE MENU . Now press themain-menu button Mode; then press the side-menu button Average 16.

c. Hook up the test-signal source: Connect, through a 50 � precisioncoaxial cable, the signal output of a sine wave generator to CH 1 (seeFigure 4–13).


Output


2. Confirm Main and Delayed trigger systems are within sensitivity limits(50 MHz):


� Set the generator frequency to 50 MHz.

� Press MEASURE.

Performance Tests


� Press the main-menu button High-Low Setup; then press theside-menu button Min-Max .


� Press the side-menu button –more– until Amplitude appears in theside menu (its icon is shown at the left). Press the side-menu button Amplitude .

� Adjust the trigger MAIN LEVEL knob to obtain stable triggered waveform.


� Set the test signal amplitude for about three and a half divisions onscreen. Now fine adjust the generator output until the CH 1Amplitude readout indicates the amplitude is 350 mV. (Readoutmay fluctuate around 350 mV.)

� Disconnect the 50 � precision coaxial cable at CH 1 and reconnectit to CH 1 through a 10X attenuator.

b. Check for Main trigger system for stable triggering at limits:

� Read the following definition: A stable trigger is one that isconsistent; that is, one that results in a uniform, regular displaytriggered on the selected slope (positive or negative). This displayshould not have its trigger point switching between opposite slopes,nor should it “roll” across the screen. At horizontal scale settings of2 ms/division and faster, TRIG’D remains constantly lit. It flashesfor slower settings.

� Press TRIGGER MENU ; then press the main-menu button Slope.

� Press SET LEVEL TO 50% . CHECK that a stable trigger isobtained for the test waveform on both the positive and negativeslopes. (Use the side menu to switch between trigger slopes; use thetrigger MAIN LEVEL knob to stabilize the trigger if required.)

� Leave the Main trigger system triggered on the positive slope of thewaveform before continuing to the next step.

Performance Tests


Set a signal withan amplitude

at the minimumtrigger sensitivity.

Check for a stabletrigger at both the

positive and negativeslope settings.

1

2

Figure 4–14: Measurement of Trigger Sensitivity

c. Check delayed trigger system for stable triggering at limits: Do thefollowing subparts in the order listed.

� Press HORIZONTAL MENU ; then press the main-menu buttonTime Base. Now press the side-menu button Delayed Only.

� Press SHIFT; then press DELAYED TRIG . Press the main-menubutton Level.

� Press the side-menu button SET TO 50%. CHECK that a stabletrigger is obtained for the test waveform for both the positive andnegative slopes of the waveform. (Use the General Purpose knob tostabilize the trigger if required.) Press the main-menu button Slope;then use the side menu to switch between trigger slopes.

� Leave the delayed trigger system triggered on the positive slope ofthe waveform before continuing to the next step. Also, return to themain time base: Press HORIZONTAL MENU ; then press themain-menu button Time Base. Now press the side-menu buttonMain Only.

3. Confirm that the Main and Delayed trigger systems are within sensitivitylimits (at upper frequency limits):

a. Hook up the test-signal source: Disconnect the hookup installed instep 1. Connect the signal output of a sine wave generator to CH 1.

Performance Tests


b. Set the Main and Delayed Horizontal Scales:

� Set the horizontal SCALE to 5 ns for the M (Main) time base.

� Press the side-menu button Delayed Only.

� Set the horizontal SCALE to 2 ns for the D (Delayed) time base.Press the side-menu button Main Only.

c. Display the test signal:

� Set the generator frequency to 350 MHz (TDS 420A) or 500 MHz(TDS 430A and TDS 460A).

� Set the test signal amplitude for about five divisions on screen. Nowfine adjust the generator output until the CH 1 Amplitude readoutindicates the amplitude is 500 mV. (Readout may fluctuate around500 mV.)

� Disconnect the sine wave at CH 1 and reconnect it to CH 1 througha 5X attenuator.

d. Repeat step 2, substeps b and c only.

4. Confirm that the Main and Delayed trigger systems couple trigger signalsfrom all channels: Doing the procedure Check Analog Bandwidth, whichbegins on page 4–25, checks coupling. If you have not done that procedure,do so after finishing this procedure. See the following note.

NOTE. Steps 1 through 3 confirmed trigger sensitivity for the Main and Delayedtriggering systems using the CH 1 input. Doing the procedure Check AnalogBandwidth ensures that trigger signals are coupled from all channels.

5. Disconnect the hookup: Disconnect the cable from the generator output atthe input connector of the channel last tested.

EquipmentRequired


Two precision 50� coaxial cables (Item 5)






Maximum InputFrequency, Auxiliary

Trigger

Performance Tests





� Set the vertical SCALE to 1 volt; set the horizontal SCALE to 20 ns.


� Press the main-menu button Coupling. Press the side-menu button� to toggle it to the 50 � setting.

� Press TRIGGER MENU . Press the main-button SOURCE; thenpress the side-menu button –more– until Auxiliary appears in theside menu. Press the side-menu button Auxiliary .

� Press the Coupling main-menu button; then press the AC side-menu button.


� Connect a BNC T connector to the output of the sine wave generator(see Figure 4–15).

� Connect one 50 � cable to one side of the BNC T connector;connect a second 50 � cable to the other side of the BNC T connector.

� Connect one of the cables just installed to CH 1; connect the othercable just installed to the AUX TRIGGER input at the rear panel.

Sine WaveGenerator

Output

To Rear PanelDigitizing Oscilloscope


Performance Tests



2. Confirm the Trigger input:


� Set the generator for a 10 MHz, four division signal.

b. Check the Main trigger system for stable triggering at limits:

� Read the following definition: A stable trigger is one that isconsistent; that is, one that results in a uniform, regular displaytriggered on the selected slope (positive or negative). This displayshould not have its trigger point switching between opposite slopes,nor should it “roll” across the screen (see Figure 4–16).

Set a signal with a fourdivision amplitude and a

10 MHz frequency.

Check for a stable triggerat both the positive andnegative slope settings.

1

2

Figure 4–16: Confirming Auxiliary Triggering at Maximum Triggering Frequency

3. Disconnect the hookup: Disconnect the cable from the generator output atthe input connector of the channel last tested.

Performance Tests


EquipmentRequired

One Function generator (Item 14)

One Sine Wave generator (Item 11)

One 50� terminator (Item 3)

One N to BNC adapter (Item 15









b. Hook up the test-signal source:

� Set the Vertical SCALE to 1 Volt per division.

� Connect the output of a function generator through a 50 � precisioncoaxial cable and a 50 � terminator to the CH 1 input.

� Set the output of the function generator for a 5 MHz, 0 to 4 Volt(4 division) square wave at the oscilloscope input.

� Move the setup from the CH 1 input to the AUX TRIGGER/EXTCLOCK input on the rear panel of the oscilloscope (see Figure 4–17).

Sine WaveGenerator

Digitizing Oscilloscope FunctionGenerator

Output

To Rear Panel

Output


Check External Clock

Performance Tests


� Connect the output of the sine wave generator through an N-to-BNCadaptor, and a 50 � precision coaxial cable to the CH 1 input of the oscilloscope.

� Set the Vertical SCALE to 100 mV.

� Press VERTICAL MENU , then press the Coupling main-menu button.

� Set the coupling to 50 �.

� Set the output of the sine wave generator for a 100 KHz 4 division sine wave.


� Press HORIZONTAL MENU , then press the Clock main-menu button.

� Press the side-menu button External.

� Set the Max Ext Clock Rate to 10.0 MHz.


d. Check external clock:

� CHECK that the displayed sine wave has a one division period.

� Slowly adjust the frequency of the function generator to 10 MHzwhile watching the display.

� CHECK that the period of the displayed sine wave changes to two divisions.


2. Disconnect the hookup: Disconnect the cables from the generators at theCH 1 and AUX TRIGGER/EXT CLOCK input connectors.

Performance Tests


EquipmentRequired

One NTSC format video generator (Item 18)

One 75 � coaxial cable (Item 6)

One 75 � terminator (Item 4)





� Press the main menu button Recall Factory Setup.

� Press the side menu button OK Confirm Factory Init .

b. Modify the default setup:




� Press the main menu button Record Length.

� Press the side menu button 5000 points in 100 divs.

c. Hook up the test-signal source: Connect, through a 75 � precisioncoaxial cable, followed by a 75 � terminator, the output of a NTSCformat video generator to CH 1 (see Figure 4–18).

Digitizing OscilloscopeVideoGenerator

75 �Terminators

Output


Check Video TriggerSensitivity

(Option 05 Equipped Models Only)

Performance Tests


2. Confirm the video trigger system is within limits:


� Set video generator to NTSC format.

� Set the output of the generator for a five step ramp with color burst.

� Press SET TO 50%. Use the trigger MAIN LEVEL knob tostabilize the display as required.


� Press the main menu button Mode & Holdoff . Then press the sidemenu button Normal.

b. Fine adjust the sync pulse amplitude: The amplitude of the TVwaveform should now be about 2 divisions pk-pk. Do the followingsubparts to fine adjust the vertical gain until the sync pulses measureexactly 0.6 divisions peak-to-peak using the graticule:


� Press the main menu button Fine Scale.

� Use the General Purpose knob, adjust the fine gain until the syncpulse amplitude is 0.6 divisions measured using the graticule (seeFigure 4–19).

Performance Tests


Adjust the sync pulseamplitude for 0.6 divisions.

Figure 4–19: Adjusting Sync Pulse Amplitude

c. Check for stable triggering against limits:

� Read the following definition: A stable trigger is one that isconsistent; that is, one that results in a uniform, regular displaytriggered on the selected slope (positive or negative). This displayshould not have its trigger point switching between opposite slopes,nor should it “roll” across the screen. At horizontal scale settingsappropriate for viewing video waveforms, the TRIG’D light remainsconstantly lit.

� Press TRIGGER MENU . Press the main menu button Typetwice — first to pop up its menu and then to toggle it to Video.

� Press the main menu button Class to pop up its menu. Press it againas needed to toggle it to NTSC.

� Press the main menu button Scan to pop up its menu.

� Press the side menu button Odd. Center the display at mid screen.

� CHECK that a stable trigger is obtained with the last two lines ofTV field 2 and the beginning of TV field 1 displayed. (If the last lineis a full TV line duration (63.5 �s), then it is the end of field 2 — seewaveform R1 in Figure 4–20.)

� Press the side menu button Even. Center the display at mid screen.

Performance Tests


� CHECK that a stable trigger is obtained with the last of TV field 1and the beginning of TV field 2 displayed. (If the last line is � of aTV line duration (31.75 �s), then it is the end of field 1 — seewaveform R2 in Figure 4–20.)

� Press the side menu button All .

� Press the main menu button Mode and Holdoff. Then press the sidemenu button Holdoff .

� Use the General Purpose knob to set the holdoff to 1.

R1 waveform: Note that twofull lines start the display

R2 waveform: Note that 1�lines start the display

R3 and R4 waveforms: Notethat with non-interlaced,both fields, scan mode,

CH 1 switches between theR3 and R4 displays

Figure 4–20: Measurement of Video Sensitivity

� Rotate the horizontal POSITION control clockwise to move theends of both fields to the center of the display.

� CHECK that a stable trigger is obtained while alternating betweenfield 1 and field 2. (If the last line is alternating between a full TVline and � a line in duration (63.5 �s and 31.75 �s respectively),then triggering is occurring on both fields — see waveforms R3 andR4 in Figure 4–20.)

d. Check delay by lines:

� Press the main-menu button Scan.

Performance Tests


� Press the side-menu button Odd.

� Rotate the horizontal POSITION control counter clockwise andalign the trigger “T” to center screen

� Press the main-menu button TV Delay Mode.

� Press the side-menu button Line.

� Use the General Purpose knob to set the line count to 10.

� CHECK that the selected line is the first line that has the color burst signal.

e. Check sync trigger:

� Using the Vertical POSITION knob, move the video waveformfrom the top to the bottom of the display.

� CHECK that the TRIG’D LED stays on and the waveform is stable.

� Using the Vertical POSITION knob return the waveform to thecenter of the display.

3. Disconnect the hookup: Disconnect the cable from the generator output atthe input connector of CH 1.

Output Signal CheckThe procedure that follows checks the characteristics of the probe compensationsignal that are listed as checked under Warranted Characteristics in Chapter 1,Specification.

EquipmentRequired

One standard-accessory 10X probe (Item 17)

Prerequisites See page 4–15. Also, this digitizing oscilloscope must have passedCheck Accuracy — Long-Term Sample Rate, Delay time, and DeltaTime Measurements on page 4–34, and Check DC Voltage Measurement Accuracy (Averaged) on page 4–22.


a. Hook up test signal: Install the standard-accessory probe on CH 1.Connect the probe tip to PROBE ADJ on the front panel; leave theprobe ground unconnected (see Figure 4–21).

Check Probe AdjustOutput

Performance Tests









� Press AUTOSET. Set the horizontal SCALE to 200 �s.

� Press SHIFT; then press ACQUIRE MENU .

� Press the main-menu button Mode; then press the side-menu buttonHi Res.

2. Confirm that the Probe Compensator signal is within limits for amplitudeand frequency:

a. Measure the amplitude and frequency of the probe compensation signal:

� Press MEASURE; then press the main-menu button SelectMeasurement for Ch1.

� Now repeatedly press the side-menu button –more– until Amplitudeappears in the side menu (its icon is shown at the left). Press theside-menu button Amplitude .

� Repeatedly press the side-menu button –more– until Frequencyappears in the side menu (its icon is shown at the left). Press theside-menu button Frequency.

Performance Tests


� Press CLEAR MENU to remove the menus from the display. SeeFigure 4–22.

Figure 4–22: Measurement of Probe Compensator Limits

b. Check against limits: CHECK that the CH 1 Freq readout is within950 Hz to 1.050 kHz, inclusive, and that the readout for Ch1 Ampl iswithin 475 mV to 525 mV, inclusive.

c. Disconnect the test hookup: Remove the test probe as desired.

Sine Wave Generator Leveling ProcedureSome procedures in this manual require a sine wave generator to produce thenecessary test signals. If you do not have a leveled sine wave generator, use oneof the following procedures to level the output amplitude of your sine wave generator.

Performance Tests


EquipmentRequired

Sine Wave Generator (Item 11)

Level Meter and Power Sensor (Item 12)

Power Splitter (Item 13)

Two Male N to Female BNC Adapters (Item 15)

One precision coaxial cable (Item 5)


Sine WaveGenerator

Digitizing Oscilloscope LevelMeter

PowerSensor

PowerSplitter

Attenuators(if necessary)

Input

Output

Figure 4–23: Sine Wave Generator Leveling Equipment Setup

1. Install the test hookup: Connect the equipment as shown in Figure 4–23.

2. Set the Generator:

� Set the sine wave generator to a reference frequency of 10 MHz.

� Adjust the sine wave generator amplitude to the required number ofdivisions as measured by the digitizing oscilloscope.

3. Record the reference level: Note the reading on the level meter.

4. Set the generator to the new frequency and reference level:

� Change the sine wave generator to the desired new frequency.

Procedure for BestAccuracy

Performance Tests


� Input the correction factor for the new frequency into the level meter.

� Adjust the sine wave generator amplitude until the level meter againreads the value noted in step 3. The signal amplitude is nowcorrectly set for the new frequency.

EquipmentRequired

Sine Wave Generator (Item 11)

Level Meter and Power Sensor (Item 12)

Two Male N to Female BNC Adapters (Item 15)



1. Install the test hookup: Connect the equipment as shown in Figure 4–24(start with the sine wave generator connected to the digitizing oscilloscope).


LevelMeter

PowerSensor

Sine WaveGenerator

Output

Input

Connect the sine wavegenerator to the

oscilloscope and thepower sensor as

directed in the text.

Figure 4–24: Equipment Setup for maximum Amplitude

2. Set the Generator:

� Set the sine wave generator to a reference frequency of 10 MHz.

� Adjust the sine wave generator amplitude to the required number ofdivisions as measured by the digitizing oscilloscope.

Alternate Procedure forMaximum Amplitude

Performance Tests


3. Record the reference level:

� Disconnect the sine wave generator from the digitizing oscilloscope.

� Connect the sinewave generator to the power sensor.

� Note the level meter reading.

4. Set the generator to the new frequency and reference level:

� Change the sine wave generator to the desired new frequency.

� Input the correction factor for the new frequency into the level meter.

� Adjust the sine wave generator amplitude until the level meter againreads the value noted in step 3. The signal amplitude is now correctly setfor the new frequency.

� Disconnect the sine wave generator from the power sensor.

� Connect the sinewave generator to the digitizing oscilloscope.


Adjustment Procedures

This chapter contains information needed to adjust the TDS 420A, TDS 430A,and TDS 460A Digitizing Oscilloscopes.

The Adjustment Procedures are divided into three parts:

� This general information about adjusting this oscilloscope and the writtenprocedures for installing and using the adjustment software.

� The TDS 420A, TDS 430A, & TDS 460A Adjustment Software included withthis manual. Read the material in this section before using the adjustment software.

� Two written procedures for manually adjusting the probe and the monitorassembly.

Use this procedure to return the oscilloscope to conformance with its WarrantedCharacteristics (they are listed starting on page 1–15). You can also use thisprocedure to optimize the performance of the oscilloscope.

This procedure is not required to verify the oscilloscope conforms with itswarranted characteristics; performance verification procedures are found in thePerformance Verification, starting on page 4–1.

As a general rule, these adjustments should be done every 2,000 hours ofoperation or once a year if used infrequently.

Requirements for PerformanceBefore you do this procedure, you need to address the following requirements.

Only trained service technicians should perform these procedures.

This oscilloscope requires a 20 minute warm-up period in a 20� C to 30� Cenvironment before it is adjusted. Adjustments done before the operatingtemperature has stabilized may cause errors in performance.

Except when adjusting the monitor assembly, the cabinet is not removed. (Amonitor adjustment is not done as part of a routine adjustment — see CompleteAdjustment on page 5–2.)

Description

Purpose

Adjustment Interval

Personnel

Warm-up Period

Access



The following computer and peripherals are required to adjust this oscilloscope;the adjustment software does not run on systems that do not meet all require-ments listed:

An IBM� PC� compatible computer equipped as follows:

� Eight MHz clock speed or faster

� MSDOS� 3.2 or higher

� 640K Resident RAM, with 580K available

� A hard drive

� A high-density floppy drive: 3.5 inch (1.44 M) or 5.25 inch (1.2 M)

� A GPIB board — National Instruments� GPIB-PCII, GPIB-PCIIA orGPIB-PCII/IIA. (A PC-GPIB package that includes the PCII/IIA isavailable — Tektronix part number S3FG210)

� Suitable keyboard and monitor

Installation of a math coprocessor in your system is strongly recommended todecrease the time required to adjust the oscilloscope.

The equipment list on page 5–5 lists all test equipment required to adjust thisoscilloscope.

UsageThe following topics cover what is required of you when adjusting the oscillo-scope and what is done by the software. Also, the performance of individualadjustments is discussed.

When using the adjustment software, you are not required to manually adjust anycircuits. The software adjusts the circuits using external standards you provide inresponse to prompts on the computer screen. Your role is to provide those testsignals and to prompt the computer to continue.

Since the probe and monitor-assembly adjustments require manual adjustment ofcircuit components, they are not part of the adjustment software. Writtenprocedures for these adjustments begin on page 5–10.

A complete adjustment is the performance of all adjustments contained in theAdjustment Software plus the probe adjustment on page 5–10. Therefore, to do a

System

Optional Peripherals

Test Equipment

Performing theAdjustments

Complete Adjustment



complete adjustment, do all adjustments in the software, completely and insequence, and then do the written probe adjustment procedure.

Throughout this chapter, “complete adjustment” is used as just defined. Note thatthe procedure Monitor Assembly Adjustment (page 5–21) is not required to do acomplete adjustment.

The adjustment software contains a sequence of individual adjustments. The listof those adjustments follows:

� Signal Path Compensation

� Voltage Reference Adjustment

� High Frequency Response Adjustment (TDS 430A and TDS 460A only)

� Low Frequency Response Adjustment

� Trigger Skew Adjustment

All these software-based adjustments are made internally by the adjustmentsoftware, and all adjustments are done without removal of the oscilloscopecabinet.

The adjustment software allows you to make individual adjustments. However,usually all adjustments are made unless you are adjusting circuits in the courseof troubleshooting the oscilloscope. Read the information under CompleteAdjustment, page 5–2, Adjustment After Repair, page 5–3, and AdjustmentDependencies, page 5–4, before doing an individual adjustment.

After the removal and replacement of a module due to electrical failure, youeither must do a complete adjustment or no adjustment is required, depending onthe module replaced. See Table 5–1.

Table 5–1: Adjustments Required for Module Replaced

Module Replaced Adjustment Required

Acquisition Board Complete Adjustment

Attenuator Board Complete Adjustment

Front Panel Assembly None Required

Low Voltage Power Supply Complete Adjustment

CPU Assembly Complete Adjustment

DSP Assembly None Required

Display Assembly None Required

Individual Adjustments

Partial Adjustment

Adjustment After Repair



Table 5–1: Adjustments Required for Module Replaced (Cont.)

Module Replaced Adjustment Required

Auxiliary Power Supply None Required

Backplane Assembly None Required

Monitor Assembly None Required

Some adjustments depend on the successful prior completion of other adjust-ments. For example, the Voltage Reference Adjustment must pass before anyother adjustments can be successfully completed. Table 5–2 lists the adjustmentsand their dependencies.

Table 5–2: Adjustments and Dependencies

Class of Adjustment Prior Completion Requirements

Voltage Reference Adjustment None

Low Frequency Response Adjustment Voltage Reference

High Frequency Response Adjustment(TDS 430A and TDS 460A only)

Voltage Reference

Trigger Adjustment Voltage Reference

Probe Adjustment Voltage Reference, Low Frequency Response,and High Frequency Response

Monitor Adjustment None

Adjustment Dependencies



Equipment RequiredThe test equipment required to adjust the TDS 420A, TDS 430A, and TDS 460ADigitizing Oscilloscopes is listed in Table 5–3.

Table 5–3: Test Equipment, Fixtures, and Supplies

Item Number andDescription Minimum Requirements Example Purpose

1. Computer System See description under Systemon page 5–2 for minimum andrecommended requirements

Standard PC, see descriptionunder System on page 5–2.

Software-based adjustments

2. Adapter, BNC-female-to-BNC-female



Probe adjustment

3. Adapter, Probe Tip toBNC, 50 � termination



Probe adjustment

4. Adjustment Tool 0.1 inch hex wrench on bothends

GC Electronics #8606 A26 Monitor adjustment

5. Attenuator, 10X (two required)

Ratio: 10X; impedance 50 �;connectors: female BNC input,male BNC output


Software-based adjustmentsand probe adjustments

6. Attenuator, 2X Ratio: 2X; impedance 50 �;connectors: female BNC input,male BNC output



7. Cable GPIB IEEE Std 488.1–1987/IEEE Std 488.2–1987



8. Cable, Precision Coaxial 50 �, 36 in, male to male BNCconnectors



9. Coupler, Dual-Input BNC female to dual male BNC Tektronix part number067-0525-02


10. Connector, Dual-Banana BNC female to dual banana Tektronix part number103-0090-00


11. Generator, DC Calibration Variable amplitude to ±10 V;accuracy to 0.05%

Wavetek 9100 (or, optionally,Data Precision 8200)


12. Probe, 10X, included withthis instrument

A P6138A Probe Tektronix P6138A Signal interconnection

13. Generator, Leveled SineWave, medium-frequency

200 kHz to 250 MHz; Variableamplitude from 5 mV to 4 Vp-pinto 50 �� flatness ≤3 %;harmonic content: 2nd harmonicdown –30 dB from fundamental;all others down –40 dB

Rohde & Schwarz SMY SineWave Generator, Rohde &Schwarz URV 35 Level Meterwith NRV–Z8 Power Sensor,and RVZ Power Splitter, (or,optionally, TEKTRONIX SG5031 or SG50302 Leveled SineWave Generator)




Table 5–3: Test Equipment, Fixtures, and Supplies (Cont.)

Item Number andDescription PurposeExampleMinimum Requirements

14. Generator, Leveled SineWave, high-frequency

250 MHz to 500 MHz; Variableamplitude from 5 mV to 4 Vp-pinto 50 �; harmonic content:2nd harmonic down –30 dB fromfundamental; all others down –40 dB

Rohde & Schwarz SMY SineWave Generator, Rohde &Schwarz URV 35 Level Meterwith NRV–Z8 Power Sensor,and RVZ Power Splitter, (or,optionally, TEKTRONIXSG 5041 Leveled Sine WaveGenerator with its leveling heador a TEKTRONIX SG 50302

Programmable Leveled SineWave Generator with its level-ing head)

Software based adjustments

15. Generator, Pulse High amplitude pulse withvariable amplitude of 60 V to 100 V

Wavetek 9100 with options 100and 250 (or, optionally, TEK-TRONIX PG 506A Calibration Generator1)

Software based adjustmentsand probe adjustment

16. Head, Pulse Generator TEKTRONIX 067-0681-01 TEKTRONIX 067-0681-01Tunnel Diode Pulser

Probe adjustment

17. Photometer 0.1 to 200 Footlamberts (0.343 to 686 Candelas)

Tektronix J17 Photometer withJ1803 Luminance Probe

Contrast adjustment

1 Requires a TM 500 or TM5000 Series Power Module Mainframe.2 Requires a TM5000 Series Power Module Mainframe.



Adjustment InstructionsThe following instructions guide you through installing the software on yoursystem, setting up the oscilloscope for adjustment, and starting the adjustment ofthe oscilloscope by the software.

1. Install the proper GPIB card (see System on page 5–2): Use the manualaccompanying your GPIB card to install and configure that card.

2. Configure the GPIB card:

a. This software is compatible with cards configured for PCII and PCIIAoperation. Table 5–4 lists the default card settings.

b. If these settings conflict with your hardware setup, see your GPIB cardmanual for alternate settings.

Table 5–4: GPIB Board Configuration1

Board Settings GPIB-PCII GPIB-PCIIA

Base I/O Address (hex) 2B8 2E1

Interrupt Line 7 7

DMA Channel 1 11 Systems using the combination card (GPIB-PCII/IIA)

can be configured as either a GPIB-PCII or aGPIB-PCIIA.

c. If you have more than one GPIB card installed, this adjustment softwareassumes the first card (referenced 0). See your GPIB card manual forinformation on how to determine which card is your “0” card.

NOTE. ALWAYS use this installation procedure when installing this software on anew computer. This installation program uses parameters you supply (see step 2,substep c) to create a custom start-up file on your hard disk directory. Afterinstallation, you will be instructed to run this start-up batch file whenever youdo software-based adjustments, so it can configure your computer properlybefore it runs the adjustment program. Do not simply copy the software filesfrom one computer to another, since the start-up batch file you copy might notmatch the computer you copy it to.

1. Create a working disk: Power on and boot your system. Using the properDOS commands, copy the adjustment software for your digitizing oscillo-scope to a working disk.

Hardware Installation

Software Installation



2. Install the software to hard disk:

a. Install your working disk in a floppy drive and switch to that drive.

b. Use the appropriate commands to display the file called README. Readthis file before continuing with this procedure.

c. Type install. Install asks you to specify the hard disk on which to installthe adjustment software. It also prompts you to specify several GPIB-card configuration parameters.

d. The adjustment software is installed in a directory called TDS400A.ADJ.

3. Store your installation disk: Remove your installation disk and store it in asecure place.

EquipmentRequired

All items that are listed for “Software-based adjustments” under“Purpose” in Table 5–3 starting on page 5–5.

1. Hook up the oscilloscope:

a. Connect the GPIB cable (Item 7) to the GPIB port at the computer rearpanel. (When multiple GPIB cards are installed, connect to the GPIB0card.)

b. Connect the GPIB cable (Item 7) to the GPIB port at the oscilloscoperear panel.

c. Power on the oscilloscope.

2. Set up the oscilloscope:

a. Press SHIFT; then press UTILITY .

b. Repeatedly press the main-menu button System until I/O is highlightedin the pop up menu.

c. Press the side-menu button TALK/LISTEN .

d. Use the General Purpose knob to set any address between 0 and 29.

3. Let the oscilloscope warm up: Allow a 20 minute warm up period before youbegin step 4.

4. Start the adjustment software:

a. Change drives to your hard drive.

b. Change directories to TDS400A.ADJ.

c. Type ADJ400A.

Software-BasedAdjustments



d. Follow the instructions as prompted on your computer screen.

NOTE. The adjustment software prompts you to enter the ambient temperature.Enter the exact ambient temperature, within ±1� C. Failure to enter thetemperature as just specified results in an adjustment of the oscilloscope that candegrade oscilloscope performance across the specified operating temperaturerange.

5. When adjustment is completed:

a. To do a complete adjustment as defined on page 5–2, do the procedureProbe Adjustment on page 5–10.



Probe AdjustmentProbe adjustment is divided into three parts: Compensate the Probe, Measure theProbe Bandwidth, and Adjust the Probe High-Frequency Response. If probebandwidth is within required limits, do not do the high frequency responseadjustment.

EquipmentRequired

The P6138A probe (Item 12)

The probe adjustment tool included as a probe accessory



Figure 5–1: Hookup for Probe Compensation

a. Hook up test-signal source: Install the standard-accessory probe toCH 1. Connect the probe tip to PROBE ADJ on the front panel; leavethe probe ground unconnected.






� Press AUTOSET. Set the horizontal SCALE to 200 �s.


Compensate the Probe




� Push the main-menu button Bandwidth. Then push the side-menubutton 20 MHz.

� Press SHIFT. Then press ACQUIRE MENU .

� Press the main-menu button Mode. Then press the side-menu button Hi Res.

2. Compensate the Probe:

a. Locate the probe compensation hole in the side of the probe body (seeFigure 5–2).

b. Using the probe compensation tool, adjust the probe for best squarewave compensation (flat as possible across the top of the waveform).(See Figure 5–3.)

Figure 5–2: Performing Probe Compensation



Probe Compensated Correctly

Probe Overcompensated

Probe Undercompensated

Figure 5–3: Proper and Improper Probe Compensation

3. Disconnect the hookup: Disconnect the probe from the probe adj (adjust)terminals; leave the probe installed on CH 1 and leave the oscilloscopecontrol setup as is for doing the next part of the probe adjustment.

EquipmentRequired

TDS 420A: one leveled sine wave generator (Item 13)

TDS 430A and TDS 460A: one leveled sine wave generator (Item 14)

One BNC female to BNC female adapter (Item 2)

One 50 � BNC to probe tip adapter (Item 3)

One P6138A 10X probe (Item 12).


a. Expose the Inner Probe Tip: Follow the instructions in Figure 5–4.


b. Hook up test-signal source:

� Connect the output of a leveled sine wave generator to a BNCfemale to BNC female adapter (see Figure 5–5).

� Connect the BNC female to BNC female adapter to a BNC to probetip adapter.

Measure the ProbeBandwidth



� Plug the probe tip from the probe on CH 1 into the BNC to probe tipadapter.

Pull forward toremove theretractable hook tip.

Unscrew the ribbedferrule tip cover and pullforward to remove.

Pull forward toremove theground-leadassembly.

3

2

1

Figure 5–4: Exposing the Inner Probe Tip

Leveled SignWave Generator


BNC Female toBNC Female

AdapterBNC to ProbeTip Adapter

Output


c. Initialize the oscilloscope:






d. Modify the initialized front-panel control settings:

� Press Autoset.


� Set the horizontal SCALE to 100 ns. (If you use a referencefrequency other than 10 MHz, set the horizontal SCALE to display5 to 7 cycles of the waveform.)


� Press the main-menu button Mode. Then press the side-menu buttonHi Res.

� Press MEASURE.

� Press the main-menu button Hi-Low Setup. Then press theside-menu button Min-Max .


� Repeatedly press the side-menu button –more– until Pk-Pk appearsin the side menu. Press the side-menu button Pk-Pk.


2. Confirm probe bandwidth:

a. Display and measure the test signal:

� Monitor the CH 1 Pk-Pk readout while you set the output of thegenerator for a 600 mV (6 division), 10 MHz or less reference signal.

� (TDS 420A Only) Set the horizontal SCALE to 2 ns and set thefrequency of the generator to 200 MHz.

� (TDS 430A and TDS 460A Only) Set the horizontal SCALE to 1 nsand set the frequency of the generator to 400 MHz.

� Read the measurement results at the CH 1 Pk-Pk readout on screen.

b. Check against limits: CHECK that the CH 1 Pk-Pk readout is greaterthan or equal to 420 mV.


a. Unplug the probe from the BNC to probe tip adapter.

b. If substep 2b was passed, the probe adjustment is finished. Reverse theinstructions in Figure 5–4, page 5–13, to reinstall the retractable hookprobe tip.



c. If substep 2b was not passed, leave the probe tip exposed. Remove theprobe from CH 1 and go on to the next procedure Adjust the ProbeHigh-Frequency Response.

Do not perform this procedure until you have first completed the proceduresCompensate the Probe and Measure Probe Bandwidth on pages 5–10 and 5–12,respectively.

Do not perform this procedure if you have successfully completed Measure theProbe Bandwidth. Probe adjustment is complete.

EquipmentRequired

One pulse generator (Item 15)

One pulse generator head (Item 16)

One 50 � precision cable (Item 8)

One BNC female to BNC female adapter (Item 2)

One 50 � BNC to probe adapter (Item 3)

One P6138A 10X probe (Item 12)


One probe adjustment tool (included with the P6138A probe accessories).


a. Access Inner Probe Tip and Adjustment Ports:

� The probe tip should be exposed from the procedure Measure ProbeBandwidth. If not, follow the instructions in Figure 5–4 to exposethe probe tip.

� Follow the instructions in Figure 5–6 to remove the probe body covers.

Adjust the Probe — HighFrequency Response



Use a small standard screw driver topry between the cover and metal cord

connector to pop off cover.

Repeat for lower cover.

Figure 5–6: Exposing the Probe Body

b. Hook up test-signal source:

� Connect the high-amplitude output of a pulse generator, through a50 � precision cable to the input of the pulse generator head (seeFigure 5–7).

� Connect the output of the pulse generator head through a 10Xattenuator to CH 1.

� Set the triggering level of the pulse generator head to minimum.

Pulse GeneratorDigitizing Oscilloscope

Pulse GeneratorHead

10X Attenuator

Precision Cable

Output


c. Initialize the oscilloscope:






d. ��

� Set vertical SCALE to 5 mV.

� Press VERTICAL MENU . Then press the main-menu buttonCoupling. Press the side-menu button � to toggle to 50 � coupling.


� Press the main-menu button Mode. Then press the side-menu buttonHi Res.


2. Adjust the Probe:

a. Display and store the reference signal:

� Set the high-amplitude output of the generator for 60 to 100 V at theinput to the pulse generator head (see Figure 5–8).

� Advance the triggering level of the pulse generator head until a fiveto six division square wave appears on screen.

� Push SET LEVEL TO 50% as required to trigger the signal.

� Advance the horizontal SCALE to 5 ns.


� Press the main-menu button Trigger Position; and press theside-menu button 10%.

� Push SHIFT. Then press SAVE WAVEFORM .

� Press the main-menu button Save Waveform. Then press theside-menu button To Ref 1.



Pulse GeneratorDigitizing Oscilloscope

BNC Female toBNC Female

AdapterBNC to ProbeTip Adapter

Output

Pulse GeneratorHead

Figure 5–8: Probe Test Hookup

� Press MORE . Then push the main-menu button Ref 1.

b. ��

� Disconnect the pulse generator head at CH 1 and remove the 10X attenuator.

� Connect the output of the pulse generator head through a BNCfemale to BNC female adapter to a BNC to probe tip adapter.

� Install the probe on CH 1.

� Plug the probe tip from the probe into the BNC to probe tip adapter.

� Press the main-menu button Coupling. Then press the side-menubutton � to toggle to 1 M� coupling.


� Press the main-menu button Trigger Position; press the side-menubutton 10%.

c. ��

� Locate the various adjustments in Figure 5–9.

� Manually adjust the front-corner response of the probe to best matchthe response of the Ref 1 waveform. Note that it is more importantto match the response during the first 5 ns than during the entire first20 ns the adjustments affect.

� See Figure 5–10 to see what areas on the front corner that thevarious adjustments affect.



LF Comp

R1 R2

C1

Not Used

Figure 5–9: Locations of Probe Adjustments

d. ��

� Redo the procedure Measure the Probe Bandwidth to check if theprobe now meets its bandwidth requirement.

� If bandwidth is met, adjustment is complete. Skip to step 3.

� If bandwidth is not met, redo this procedure, increasing front cornerovershoot slightly relative to the stored waveform.

� Repeat this step (d) until bandwidth is met.



5 nsC1

20 nsR1

10 nsR2

1. Adjust R1 for best overall match.

2. Adjust R2 and C1 for best match betweenfront corners.

3. Repeat the first two steps as needed dueto interaction between adjustments.

5 nsC1

20 nsR1

10 nsR2

Positive Pulse

Negative Pulse

Figure 5–10: Adjustments vs. Front-Corner Response

3. �� Unplug the probe from the BNC to probe tipadapter. Reverse the instructions in Figure 5–4, page 5–13, to reinstall theretractable probe tip.



Monitor Assembly Adjustment

WARNING. High voltages are accessible on the A26 Monitor assembly. Do nottouch the circuit board when the power is on. Do not touch the CRT anodebutton even if the power is off. Wear safety glasses when working with the CRT.

Do not do this procedure when performing a routine adjustment. Only do thisprocedure if the display on the monitor assembly has become unsatisfactory. SeeComplete Adjustment on page 5–2.

CAUTION. Static electricity can damage this circuitry. When standing the CRT onits front panel place it on a clean padded surface.

The equipment required to do this procedure is listed in Table 5–3.

EquipmentRequired

One J17 Photometer with a J1803 Luminance Probe (Item 17)

One monitor adjustment tool (Item 4)

1. Access the inside of the oscilloscope: See the Removal and InstallationProcedures starting on page 6–9 to remove the cabinet.

2. Adjust the vertical and horizontal sync:

a. If the display rolls vertically adjust V. SYNC (R453) to the center of thestable display range. (See Figure 5–11.)

b. If diagonal lines are present on the display adjust H. SYNC (R473) tothe center of the stable display range.



3. Adjust the display brightness:

a. Display the Circle test pattern:

� Disconnect the power plug from the oscilloscope.

� Set the DIP switch (S1), located near the front of the A03 CPUboard, as follows:

Switch No. 1 2 3 4 5 6 7 8

Open X X

Closed X X X X X X

� Reconnect the power plug to the oscilloscope.

� Power on the oscilloscope.

� Allow 15 to 20 minutes for the oscilloscope to warm up.

� Press SHIFT and UTILITY .

� Repeatedly press the main-menu button System until Diag/Err ishighlighted in the pop up menu.

� Repeatedly press the main-menu button Area until Display ishighlighted in the pop up menu.

� Repeatedly press the side-menu button –more– until Circle appearsin the side menu. Push Circle.

� Press the main-menu button EXECUTE . Then press the side-menubutton Ok Confirm Run Test.

b. Make the brightness adjustment:

� Locate R482 (BRITE) (see Figure 5–11).

� Adjust R482 until the background raster lines in the 5% luminancepatch (see Figure 5–12 on page 5–24) disappear while the lines inthe 10% luminance patch are visible.



H. PHASE (463)

Front of the Oscilloscope

Left Side of theOscilloscope

V. POS (R445)

VID. GAIN (R483)

BRITE (R482)

H. SYNC (R473)

V. LIN (R462)

V. SYNC (R453)

V. SIZE (R452)

H. LIN (L400)

H. SIZE (L310)

FOCUS (R411)

Figure 5–11: Monitor Adjustment Locations

4. Adjust the display contrast:

a. Display the White Box test pattern:

� Press the center main-menu button to display the main-menu.

� Press the main-menu button Tests.

� Repeatedly press the side-menu button –more– until White Boxappears in the side menu. Push White Box.




10%Patch

5%Patch

Figure 5–12: Five and Ten Percent Luminance Patches

b. Make the contrast adjustment:

� Locate R483 (VID. GAIN) on the A26 Monitor assembly (seeFigure 5–11).

� Monitor the luminance at center screen using a J17 photometer and aluminance probe.

� Adjust R483 (VID. GAIN) for a reading of 100 foot-lamberts(343 candelas).

� If R483 needed a large adjustment, perform the brightness adjust-ment again.

5. Adjust the display focus:

a. Display the Composite test pattern:

� Press the center main-menu button to display the main-menu.

� Press the main-menu button Tests.

� Repeatedly press the side-menu button –more– until Compositeappears in the side menu. Push Composite.




b. Make the focus adjustment:

� Locate R411 (FOCUS) (see Figure 5–11).

� Adjust R411 for best overall focusing at all four corners and at thecenter of the screen (see Figure 5–13).

CenterCorner

Corner

Corner

Corner

Figure 5–13: Composite Pattern for Focusing

6. Restore the oscilloscope to normal operation:

a. Restore the dip switch to the settings that follow:

Switch No. 1 2 3 4 5 6 7 8

Open

Closed X X X X X X X X



b. Power off the oscilloscope.

c. See the Removal and Installation Procedures starting on page 6–9 toreinstall the cabinet and other modules removed in step 1.


Maintenance

This chapter contains the information needed to do periodic and correctivemaintenance on the TDS 420A, TDS 430A, & TDS 460A Digitizing Oscillo-scopes. Specifically, the following sections are included:

� Preparation — General information on preventing damage to internalmodules when doing maintenance.

� Inspection and Cleaning — Information and procedures for inspecting theoscilloscope and cleaning its external and internal modules.

� Removal and Installation Procedures — Procedures for the removal ofdefective modules and replacement of new or repaired modules. Alsoincluded is a procedure for disassembly of the oscilloscope for cleaning.

� Troubleshooting — Information for isolating failed modules. Included areinstructions for operating the internal diagnostic routines and troubleshootingtrees. Most of the trees make use of these internal diagnostic routines tospeed fault isolation to a module.

Service personnel must be prepared to safely service the oscilloscope. Thismanual is for qualified service personnel only. Read the General Safety Summaryand the Service Safety Summary at the front of this manual. If you are unfamiliarwith the operation of this oscilloscope, read Operating Information (Chapter 2)before servicing the oscilloscope. To prevent electro-static damage (ESD), readPreventing ESD, on page 6–2, before servicing the oscilloscope.

Related Maintenance ProceduresThe following chapters contain information and procedures related to doingmaintenance.

� Chapter 2, Operating Information, covers instructions useful when operatingthe oscilloscope in order to troubleshoot it. The chapter also details theservice strategy and lists options for obtaining maintenance service and forreplacing failed modules.

� Chapter 3, Theory of Operation, contains a circuit description at the module,or block, level.

� Chapter 4, Performance Verification, contains procedures that are useful inisolating problems to modules by testing oscilloscope performance.

Maintenance


� Chapter 5, Adjustment Procedures, addresses after repair adjustment and theinterval between periodic adjustments. It contains a procedure for adjustingthe internal circuits of the oscilloscope.

� Chapter 9, Diagrams, contains a block diagram using individual modules asblocks and an interconnection diagram showing connections between themodules.

� Chapter 10, Mechanical Parts List, lists all field replaceable modules by partnumber.

PreparationThis section gives general information on preventing damage to internal moduleswhen doing maintenance.

CAUTION. Static discharge can damage any semiconductor component in thisoscilloscope.

When performing any service which requires internal access to the oscilloscope,adhere to the following precautions to avoid damaging internal modules and theircomponents due to electrostatic discharge (ESD).

1. Minimize handling of static-sensitive modules.

2. Transport and store static-sensitive modules in their static protectedcontainers. Label any package that contains static-sensitive modules.

3. Discharge the static voltage from your body by wearing a grounded antistaticwrist strap while handling these modules. Do service of static-sensitivemodules only at a static-free work station.

4. Do not remove the oscilloscope cabinet unless you have met precautionnumber 3, above. Consider all internal modules static-sensitive.

5. Nothing capable of generating or holding a static charge should be allowedon the work station surface.

6. Handle circuit boards by their edges when possible.

7. Do not slide the modules over any surface.

8. Avoid handling modules in areas that have a floor or work-surface coveringcapable of generating a static charge.

9. Do not use high-velocity compressed air when cleaning dust from modules.

Preventing ESD

Maintenance


Table 6–1 lists the relative susceptibility of various classes of semiconductors.Static voltages of 1 kV to 30 kV are common in unprotected environments.

Table 6–1: Relative Susceptibility to Static-Discharge Damage

Semiconductor ClassesRelative SusceptibilityLevels1

MOS or CMOS microcircuits or discrete circuits, or linearmicrocircuits with MOS inputs (most sensitive)

1

ECL 2

Schottky signal diodes 3

Schottky TTL 4

High-frequency bipolar transistors 5

JFET 6

Linear microcircuits 7

Low-power Schottky TTL 8

TTL (least sensitive) 91 Voltage equivalent for levels (voltage discharged from a 100 pF capacitor through

resistance of 100 ohms)�1 = 100 to 500 V 6 = 600 to 800 V2 = 200 to 500 V 7 = 400 to 1000 V (est.)3 = 250 V 8 = 900 V4 = 500 V 9 = 1200 V5 = 400 to 600 V

Susceptibility to ESD

Maintenance


Inspection and CleaningInspection and Cleaning describes how to inspect for dirt and damage on, andhow to clean the exterior and interior of, the TDS 420A, TDS 430A, &TDS 460A Digitizing Oscilloscopes. Inspection and cleaning are done aspreventive maintenance. Preventive maintenance, when done regularly, mayprevent oscilloscope malfunction and enhance its reliability.

Preventive maintenance consists of visually inspecting and cleaning theoscilloscope and using general care when operating it.

How often to do maintenance depends on the severity of the environment inwhich the oscilloscope is used. A proper time to perform preventive maintenanceis just before oscilloscope adjustment.

The cabinet helps keep dust out of the oscilloscope, and it is a major componentof the oscilloscope cooling system. The cabinet should normally be in placewhen operating the oscilloscope. The front cover protects the front panel anddisplay from dust and damage. Install the front cover when storing or transport-ing the oscilloscope.

Inspect and clean the oscilloscope as often as operating conditions require. Thecollection of dirt on components inside can cause them to overheat and break-down. (Dirt acts as an insulating blanket, preventing efficient heat dissipation.)Dirt also provides an electrical conduction path that could cause an oscilloscopefailure, especially under high-humidity conditions.

CAUTION. Avoid the use of chemical cleaning agents which might damage theplastics used in this oscilloscope. Use only deionized water when cleaning themenu buttons or front-panel buttons. Use a 75% isopropyl alcohol solution as acleaner and rinse with deionized water. Before using any other type of cleaner,consult your Tektronix Service Center or representative.

Avoid the use of high pressure compressed air when cleaning dust from theinterior of this instrument. (High pressure air can cause ESD.) Instead, use lowpressure compressed air (about 9 psi).

Inspection — Exterior. Using Table 6–2 as a guide, inspect the outside of theoscilloscope for damage, wear, and missing parts. Oscilloscopes that appear tohave been dropped or otherwise abused should be checked thoroughly to verifycorrect operation and performance. Immediately repair defects that could causepersonal injury or lead to further damage to the oscilloscope.

General Care

Inspection and CleaningProcedures

Maintenance


Table 6–2: External Inspection Check List

Item Inspect For Repair Action

Cabinet, front panel,and cover

Cracks, scratches, deformations,damaged hardware or gaskets.

Replace defective module.

Front-panel knobs Missing, damaged, or looseknobs.

Repair or replace missing ordefective knobs.

Connectors Broken shells, cracked insulation,and deformed contacts. Dirt inconnectors.

Replace defective modules.Clear or wash out dirt.

Carrying handle, bail,cabinet feet.

Correct operation. Replace defective module.

Accessories Missing items or parts of items,bent pins, broken or frayedcables, and damaged connec-tors.

Replace damaged or missingitems, frayed cables, and defec-tive modules.

Cleaning Procedure — Exterior. Use the following procedure to clean the exteriorof the oscilloscope.

CAUTION. To prevent getting moisture inside the oscilloscope during externalcleaning, use only enough liquid to dampen the cloth or applicator.

1. Remove loose dust on the outside of the oscilloscope with a lint free cloth.

2. Remove remaining dirt with a lint free cloth dampened in a general purposedetergent-and-water solution. Do not use abrasive cleaners.

3. Clean the monitor screen with a lint-free cloth dampened with either isopro-pyl alcohol or, preferably, a gentle, general purpose detergent-and-watersolution.

Inspection — Interior. To access the inside of the oscilloscope for inspection andcleaning, refer to the Removal and Installation Procedures on page 6–9.

Inspect the internal portions of the oscilloscope for damage and wear usingTable 6–3 as a guide. Defects found should be repaired immediately.

If any electrical module is replaced, check Table 5–1 on page 5–3 to see if it isnecessary to adjust the oscilloscope.

CAUTION. To prevent damage from electrical arcing, ensure that circuit boardsand components are dry before applying power to the oscilloscope.

Maintenance


Table 6–3: Internal Inspection Check List

Item Inspect For Repair Action

Circuit boards Loose, broken, or corrodedsolder connections. Burnedcircuit boards. Burned, broken, orcracked circuit-run plating.

Remove failed module andreplace with a fresh module.

Resistors Burned, cracked, broken, blis-tered condition.

Remove the module with thefaulty resistor and replace it witha fresh module.

Solder connections Cold solder or rosin joints. Resolder joint and clean withisopropyl alcohol.

Capacitors Damaged or leaking cases.Corroded solder on leads orterminals.

Remove the module with thefaulty capacitor and replace itwith a fresh module from thefactory.

Semiconductors Loosely inserted in sockets.Distorted pins.

Firmly seat loose semiconduc-tors. Remove devices that havedistorted pins. Carefully straight-en pins (as required to fit thesocket), using long-nose pliers,and reinsert firmly. Ensure thatstraightening action does notcrack pins, causing them tobreak off.

Wiring and cables Loose plugs or connectors.Burned, broken, or frayed wiring.

Firmly seat connectors. Repair orreplace modules with defectivewires or cables.

Chassis Dents, deformations. Straighten, repair, or replacechassis.

Cleaning Procedure — Interior. Use the following procedure to clean the interiorof the oscilloscope.

STOP. If, after doing steps 1 and 2, a module is clean upon inspection, skip theremaining steps.

1. Blow off dust with dry, low-pressure, deionized air (approximately 9 psi).

2. Remove any remaining dust with a lint free cloth dampened in isopropylalcohol (75% solution) and rinse with warm deionized water. (Acotton-tipped applicator is useful for cleaning in narrow spaces and on circuitboards.)

Maintenance


3. If steps 1 and 2 do not remove all the dust or dirt, the oscilloscope may bespray washed using a solution of 75% isopropyl alcohol by doing steps 4through 8.

4. Gain access to the parts to be cleaned by removing easily accessible shieldsand panels (see Removal and Installation Procedures on page 6–9).

5. Spray wash dirty parts with the isopropyl alcohol and wait 60 seconds for themajority of the alcohol to evaporate.

6. Use 49� to 60� C (120� to 140� F) deionized water to thoroughly rinse the parts.

7. Dry all parts with low-pressure, deionized air.

8. Dry all components and assemblies in an oven or drying compartment using52� to 65� C (125� to 150� F) circulating air.

Lubrication. There is no periodic lubrication required for this oscilloscope.

Maintenance



Removal and Installation Procedures

This section contains procedures for removal and installation of all mechanicaland electrical modules. Any electrical or mechanical module, assembly, or partlisted in Chapter 10 of this manual is a module.

Preparation — Please Read

WARNING. Before doing this or any other procedure in this manual, read theSafety Summary found at the beginning of this manual. Also, to prevent possibleinjury to service personnel or damage to oscilloscope components, read BeforeServicing, page xvi, Supplying Operating Power, page 2–1, and Preventing ESDin this chapter.

This section contains the following information:

� This preparatory information that you need to properly do the proceduresthat follow.

� A list of equipment required to remove all modules.

� Procedures for removal and reinstallation of the electrical and mechanicalmodules.

� A disassembly procedure for removal of all the major modules from theoscilloscope at one time and for reassembly of those modules into theoscilloscope. A complete disassembly is normally only done when complete-ly cleaning the oscilloscope. (Instructions for doing the actual cleaning arefound under Inspection and Cleaning beginning on page 6–4.)

� Three module locator diagrams for finding all the modules in this oscillo-scope.

WARNING. Before doing any procedure in this section, disconnect the power cordfrom the line voltage source. Failure to do so could cause serious injury or death.

Chapter 10 lists all modules.List of Modules



Usually cables are partially or completely removed as in the course of removinga module they plug into. However, all field replaceable cables are modules andcan be replaced by doing the Access Procedure. Figure 6–4, on page 6–22, showsthe cables and their routing.

STOP. READ THESE GENERAL INSTRUCTIONS BEFORE REMOVING AMODULE.

First read over the Summary of Procedures that follows to understand how theprocedures are grouped. Then read Equipment Required for a list of the toolsneeded to remove and install modules in this oscilloscope.

Reference Figure 6–1 on page 6–11. Procedures refer to “front,” “rear,” “top,”etc. of the oscilloscope; note from the figure which sides are referenced.

If you are disassembling this oscilloscope for cleaning, go to the procedureDisassembly for Cleaning on page 6–65.

If you are removing a module for service, begin by doing the procedure AccessProcedure (page 6–13). By following the instructions in that procedure, youremove the module to be serviced while removing the minimum number ofadditional modules.

The procedures are described in the order in which they appear in this section. Inaddition, you can look up any procedure for removal and reinstallation of anymodule in the Table of Contents of this manual.

� The Access Procedure on page 6–13 first directs you to the procedure(s) thatremove any modules that must be removed to access the module to beserviced. It then directs you to the procedure to remove that module.

� Procedures for Module Removal and Installation on page 6–23 are theprocedures for removing modules. These procedures assume you have donethe access procedure.

� Disassembly for Cleaning on page 6–65 is a procedure, based on the moduleremoval procedures just described, that removes all modules for cleaning.Instructions for cleaning are found in Inspection and Cleaning beginning onpage 6–4. The Disassembly for Cleaning procedure does not use the access procedure.

Cable Removal

General Instructions

Summary of Procedures



NOTE. Read the cleaning procedure before disassembling the oscilloscope forcleaning.

Figure 6–1: Oscilloscope Orientation



Equipment Required. Table 6–4 lists the tools required to completely disassemblethe oscilloscope into its modules. The tools required to remove an individualmodule are listed in the first step of its procedure.

All the tools are standard tools readily available from tool suppliers.

Table 6–4: Tools Required for Module Removal

ItemNo. Name Description

1 Screwdriver handle Accepts Torx�-driver bits.

2 T-15 Torx tip Torx�-driver bit for T-15 size screw heads.

3 T-20 Torx tip Torx�-driver bit for T-20 size screw heads. Usedonly for removal of the cabinet handle.

4 Torque wrench 8 inch-lbs torque; accepts Torx�-driver bits.

5 Flat-bladed screwdriver Screwdriver for removing standard-headed screws.

6 Pozidriv screwdriver Used for removing disk drive.

7 Needle-Nose Pliers Standard tool. Used for removing EMI gaskets.

8 Duck-bill pliers 4 inch. Used for removing the low voltage powersupply.

9 Nutdriver, 5�16 inch Used for removing earth ground cables.

10 Angle-Tip Tweezers Used for knob and shaft removal.

11 Flat-bladed spudger A probe-like tool with a tip like a flat bladedscrewdriver. Used to press EMI gaskets into place.

12 Soldering Iron 15 watt. Used for removal of some cables and theacquisition assembly.

13 Slip-jaw pliers Used for removing the front feet from the cabinet.

14 Front cover This optional accessory protects the front of theoscilloscope when positioned face down in theremoval procedures.



Access ProcedureBegin with this procedure when you have identified a module to be removed forservice and have read General Instructions found earlier in this section.

1. Locate module to be removed:

a. Find the module to be removed in the module locator diagrams, figures6–2, 6–3, and 6–4 (pages 6–16, 6–19, and 6–22, respectively).

b. Note the number of the figure in which you found the module and themodule name.

2. Access the module:

a. If you have located the module to be replaced in Figure 6–2, do thefollowing subparts:

� Go to Table 6–5 on page 6–15.

� Find the procedure that includes the name of the module noted in step1.

� Perform the access instructions listed for the procedure found toaccess and remove the module.

� Skip to the end of this procedure (step 3) for reinstallation instructions.

b. If you have found the module to be removed in either Figure 6–3 orFigure 6–4, cabinet removal is required:

� First do Line Fuse and Line Cord on page 6–25, removing only theline cord.

� Then do Front Cover, Rear Cover, Cabinet, Rear EMI Gasket, andCabinet Handle and Feet on page 6–26, removing only the rearcover and cabinet.

� Continue with step 2c.

c. If you have located the module to be replaced in Figure 6–3, do thefollowing subparts:


� Find the procedure that includes the name of the module noted in step1.

� Perform the access instructions listed for the procedure found toaccess and remove the module.



� Skip to the end of this procedure (step 3) for reinstallation instructions.

d. If you have located the module to be replaced in Figure 6–4, you areremoving one of the field replaceable cables. Do the following subparts:


� Find the procedure that includes the name of the cable noted in step 1.

� Perform the instructions listed in the table for that procedure toaccess and remove the cable.

� Follow the instructions listed in the table for the reinstallation of thecable. Then exit this procedure.

3. Reinstall all modules removed: Read the instructions found at the end of theprocedure that removes the module to be serviced — they guide you inreinstalling all modules removed. All procedures are found under Proceduresfor Module Removal and Installation on page 6–23, which follows thisaccess procedure.



Table 6–5: Access Instructions for Modules in Figure 6–2

Procedure Including Module to be RemovedPageNo Access Instructions

1 Front-Panel Knobs and Shafts 6–23 1 Do only the procedure listed at left.

2 Remove only the module you want to service.

2 Line Fuse and Line Cord 6–25 1 Do only the procedure listed at left.

2 Remove only the module you want to service.

3 Front Cover, Rear Cover, Cabinet, Rear EMIGasket, and Cabinet Handle and Feet

6–26 1 Do Line Fuse and Line Cord removing only the line cord.

2 Do the procedure listed at left, removing only the module(s) youwant to service.

4 Trim Ring, Menu Elastomer, Menu Buttons,and Front EMI Gaskets

6–30 1 Do Line Fuse and Line Cord removing only the line cord.

2 Do Front Cover, Rear Cover, Cabinet, Rear EMI Gasket, andCabinet Handle and Feet, removing only the rear cover andcabinet.

3 Do the procedure listed at left, removing all modules including themodule(s) you want to service.

5 Disk Drive 6–33 1 Do Line Fuse and Line Cord removing only the line cord.

2 Do the Front Cover, Rear Cover, Cabinet, Rear EMI Gasket, andCabinet Handle and Feet.

3 Do the procedure listed at left to remove the module.

6 A06 Front-Panel Assembly, ESD Shield, andMenu Flex and Probe Code Flex Circuits

6–34 1 Do Disk Drive.

2 Do Trim Ring, Menu Elastomer, Menu Buttons, and Front EMIGaskets.

3 Do the procedure listed at left, removing all modules including themodule(s) you want to service.

When doing the procedure listed at left, do not remove the menuflex circuit unless it is being replaced with a new module.



HandleAssembly

FrontFoot (2)

Rear EMIGasket

Line Cord

Rear Cover

Front Cover(optional)

ESD Shield

Trim Ring

Menu FlexCircuit

A06 Front PanelAssembly

Front Panel Knobs

Front EMIGaskets (4)

Probe CodeFlex Assembly

Cabinet

Menu Button

MountingScrew

Front Panel Shafts

Fuse CapLine Fuse

MenuElastomer

DiskDrive

Figure 6–2: Cabinet and Front-Panel Mounted Modules



Table 6–6: Access Instructions for Modules in Figure 6–3

Procedure Including Module to be RemovedPageNo Access Instructions

1 A05 Attenuator Assembly and Shield 6–38 1 Do Trim Ring, Menu Elastomer, Menu Buttons, and Front EMIGaskets (page 6–30).

2 Do A08 Jumper Board Assembly, D1 Bus, and Board Supports,listed as procedure number 3 in this table. Remove only the A08jumper board assembly.

3 Do A06 Front-Panel Assembly, ESD Shield, and Menu Flex andProbe Code Flex Circuits (page 6–34). Do not remove the menuflex circuit.


2 A26 Monitor Assembly 6–40 1 Do the procedure listed at left to remove the module.

3 A08 Jumper Board Assembly, D1 Bus, andBoard Supports

6–43 1 Do the procedure listed at left to remove the module.

4 A03 CPU Assembly 6–44 1 Do A08 Jumper Board Assembly, D1 Bus, and Board Supports,removing only the board supports.


5 A02 Display Assembly 6–46 1 Do A08 Jumper Board Assembly, D1 Bus, and Board Supports.Do not remove the A08 jumper board assembly.


6 A09 DSP Assembly 6–47 1 Do A08 Jumper Board Assembly, D1 Bus, and Board Supports.Do not remove the A08 jumper board assembly.


7 A01 Backplane Assembly and its Mount 6–49 1 Do A08 Jumper Board Assembly, D1 Bus, and Board Supports.Do not remove the A08 jumper board assembly.

2 Do, in order, the procedures numbered 4-6 (inclusive) in this table.


8 Fan and Fan Mount 6–57 1 Do the procedure listed at left to remove the module.

9 A25 Low Voltage Power Supply and its Mount 6–54 1 Only if removing the plastic mount that secures the Low VoltagePower Supply, do, in order, the procedures numbered 4–7(inclusive) in this table.

2 Do procedure Fan and Fan Mount. Do not remove the fan mount.


10 A07 Auxiliary Power Supply 6–61 1 Do the procedure listed at left to remove the module.

11 Line Filter 6–59 1 Do the procedure listed at left to remove the module.



Table 6–6: Access Instructions for Modules in Figure 6–3 (Cont.)

Procedure Including Module to be Removed Access InstructionsPageNo

12 Back-Up Batteries 6–52 1 Do the procedure listed at left to remove the module.

13 A04 Acquisition Assembly 6–63 1 Do A08 Jumper Board Assembly, D1 Bus, and Board Supports(see page 6–43). Do not remove the board supports.




Figure 6–3: Internal Modules

A26 MonitorAssembly

Fan Mount

A07 AuxiliaryPower Supply

MountingScrew

Line Filter

A01 BackplaneAssembly

Option 13(Serpar)Assembly

A02 Display Assembly

MountingScrews

A09 DSP Assembly

Board Support (3)

A04 Acquisition Assembly

Mounting Screw

A08 Jumper Assembly

A05 AttenuatorAssembly

MountingScrew

Mounting Screw

BNC Connector

Mounting Screws

Battery (2)

BatteryClamp (2)

CableRetainer

Mounting Screw

Mount: Backplaneand LV Power Supply

AttenuatorShield

D1 Bus

A03 CPU Assembly

A25 Low Voltage PowerSupply AssemblyFan

MountingScrew



Table 6–7: Access (and Removal) Instructions for Cables in Figure 6–4

Name of Cable Access and Removal Instructions

1 Disk to CPU 1 Lift up on the latch at each side of both jacks.

2 Unplug the cable to be replaced from the disk drive and A03 CPUassemblies. See Figure 6–4 on page 6–22 for jack location.

3 Reverse these instructions to install the replacement cable.

2 Backplane to Acquisition

Backplane to Attenuator

1 Find the procedure A01 Backplane Assembly and its Mount in Table6–6.

2 Follow the access instructions found there to access and remove thebackplane assembly.

3 Unsolder the cable(s) to be replaced using a 15 watt soldering iron andremove it.


3 Backplane to Front Panel

CPU to Front Panel

1 Find the procedure A06 Front-Panel Assembly, ESD Shield, and MenuFlex and Probe Code Flex Circuits in Table 6–6.

2 Follow the access instructions found there to access and remove thefront panel assembly. The cables plugged into that assembly areremoved in the process.

3 Unplug the cable to be replaced from the backplane assembly. SeeFigure 6–4 for jack location.


4 Backplane to Low Voltage Power Supply 1 Reach in from the top of the oscilloscope and unplug the cable at thejacks at the front of the backplane and low voltage power supplymodules.


5 Aux Supply to Line Filter

Aux Supply to Low Voltage Power Supply

1 Find the procedure A07 Auxiliary Power Supply in Table 6–6.

2 Follow the access instructions found there to access and remove theauxiliary power supply assembly.

3 Unsolder the cable to be replaced using a 15 watt soldering iron andremove it from the auxiliary power supply.




Table 6–7: Access (and Removal) Instructions for Cables in Figure 6–4 (Cont.)

Name of Cable Access and Removal Instructions

6 Aux Supply to Low Voltage Power Supply toGround Lug

Line Filter to Ground Lug

1 If removing the aux supply to low voltage power supply to ground lugcable, unplug the cable from the low voltage power assembly. Alsounsolder the cable wires from the auxiliary power supply assembly.

2 If removing the line filter to ground lug cable, unplug it from the linefilter lug. See Figure 6–4.

3 Using a 5�16 inch nut driver (Item 9) remove the nut(s) that secure thecable to be removed from the lug and remove it.


7 Monitor 1 Find the procedure A02 Display Assembly in Table 6–6.

2 Follow the access instructions found there to access and remove thedisplay assembly. The cable is unplugged from that assembly in theprocess.

3 Unplug the cable from the monitor. See Figure 6–4 for jack location.

4 Unplug the cable from the auxiliary power supply. See Figure 6–4 forjack location.




Backplane to LowVolt. Power Supply

Monitor Cable

Backplane toAux Power

Supply

Aux Supply toLine Filter

Line Filter toGround Lug Aux Supply to Low

Voltage Power Supplyto Ground Lug

D1 Bus

Backplane to Attenuator(Soldered at Backplane)

CPU to FrontPanel

Backplane to Acquisition(Soldered at Backplane)

Backplane toFront Panel

Disk Drive toDisplay

Figure 6–4: Cables and Cable Routing



Procedures for Module Removal and InstallationDo the Access Procedure (page 6–13) before doing any procedure in this section.

1. Assemble equipment and locate modules to be removed: Have handy a pairof angled-tip tweezers (Item 10). Find the knob(s) to be removed on the frontpanel.

2. Orient the oscilloscope: Set the oscilloscope so its bottom is down on thework surface and its front is facing you.

3. Remove the knob(s): Refer to Figure 6–5 while doing the followingsubsteps.

a. Grasp any knob you wish to remove and pull it straight out from thefront panel slightly to create some clearance between the base of theknob and the front panel.

b. Insert the tweezers between the knob and front panel and use them toremove the knob and its shaft.

4. Disassemble the knob and shaft: Pull the shaft out of the knob.

5. Reinstallation:

a. To reinstall, align the inside of the knob to the end of the shaft and pushit in until it snaps.

b. Insert the shaft of the assembled knob into its hole in the front panelassembly until it stops.

c. Rotate the knob while lightly pushing inwards until the shaft slips intoits receptacle. Push the knob all the way in to seat the knob assembly.

Front-Panel Knobs andShafts



When reinstalling the knobs,note there are two sizes. Be

sure to reinstall the proper sizeknob in the proper location.

Figure 6–5: Knob and Shaft Removal



WARNING. Unplug the line cord from the line voltage power source beforecontinuing. Failure to do so can cause death or injury.

1. Assemble equipment and locate modules to be removed: Have handy aflat-bladed screwdriver (Item 5). Locate the line fuse and line cord in thelocator diagram Cabinet and Front-Panel Mounted Modules, Figure 6–2 onpage 6–16.

2. Orient the oscilloscope: Set the oscilloscope so its bottom is down on thework surface and its rear is facing you. If you are servicing the line cord, dothe next step; if you are servicing the line fuse, skip to step 5.

3. Remove line cord:

a. Find the line cord on the rear cover. (See Figure 6–6.)

Unplug1

Rotate2

3Pull

Line FuseLine Cap

Figure 6–6: Line Fuse and Line Cord Removal

Line Fuse and Line Cord



b. Now, remove the line-cord retaining clamp by first unplugging the linecord from its receptacle.

c. Next, grasp both the line cord and the retaining clamp and rotate them90 degrees counter-clockwise.

4. Pull the line cord and clamp away to complete the removal.

5. Remove line fuse: Find the fuse cap on the rear panel. (See Figure 6–6.)Now, remove the fuse cap by turning it counter clockwise using a flat-bladedscrewdriver, and remove the line fuse.

6. Reinstallation: Do in reverse steps 3 and 5 to reinstall the line fuse and thenthe line cord.

1. Assemble equipment and locate modules to be removed:

a. Have handy a screwdriver with size T-15 and T-20 Torx� tips (Items 1,2, and 3). If removing the EMI gasket at the inside rear of the cabinet,also have handy a pair of needle-nose pliers (Item 7).

b. Make sure the oscilloscope front cover is installed; if it is not, install itby snapping its edges over the trim ring.

c. Locate the rear cover and cabinet in the locator diagram Cabinet andFront-Panel Mounted Modules, Figure 6–2 on page 6–16.

2. Orient the oscilloscope:

a. Pull out on both of the hubs on the cabinet handle to unlock it forpositioning. While holding the hubs unlocked, rotate the handle towardsthe bottom of the oscilloscope.

b. Set the oscilloscope so its face is down with its front cover on the worksurface and its bottom facing you. Reference Figure 6–7 on page 6–27 asyou do the following steps.

3. Remove the front feet: If removing a front foot for replacement, use a pair ofslip-jaw pliers to firmly grip the foot, then pull with a turning motion toremove. Reverse the process to install the replacement foot. If no othermodules are being serviced, skip to the end (step 8) of this procedure.

4. Remove rear cover: Remove the four T-15 Torx� screws securing the rearcover to the oscilloscope. Lift off the rear cover. If no other modules arebeing serviced, skip to the end (step 8) of this procedure.

Front Cover, Rear Cover,Cabinet, Rear EMI Gasket,

and Cabinet Handle andFeet



EMI Gasket: Access fromthe front of the cabinet.

Front Foot: Rotateand remove.

Handle Assembly:Remove the internalscrews and pull outhandle hubs to remove.

Mounting Screws (4)

Label

Label

Mounting Screw

Figure 6–7: Front Cover, Rear Cover, Cabinet, EMI Gasket, and Cabinet Handle and Feet Removal



5. Remove the cabinet:

a. Remove the T-15 Torx� screw at the left side of the oscilloscope.

b. Grasp the two handle handle hubs and pull them outward as if to rotatethe handle.

c. While holding the handle hubs pulled out, lift the cabinet upwards toslide it off the oscilloscope.

d. At the rear of the cabinet, grasp its left and right edges. Take care not tobind or snag the cabinet on the internal cabling as you remove thecabinet.

e. If no other cabinet modules are being serviced, skip the rest of thisprocedure.

6. Remove the handle assembly: If removing the handle assembly for cleaningor replacement, do the following substeps:

a. Working from the inside of the cabinet, remove the T-20 Torx� screwsecuring each handle hub to the cabinet.

b. Working from the outside of the cabinet, grasp the two handle hubs andpull them outward from the cabinet until they are out of the cabinet.

c. While holding the handle hubs pulled out, lift the handle away toremove.

STOP. DO NOT do step 7 to remove the EMI gasket from the rear of the cabinetunless it must be replaced due to damage. If you are not replacing that gasket,skip to step 8.

When reinstalling the EMI gasket and the oscilloscope cabinet, carefully followthe instructions given. Unless the instructions are performed properly, theoscilloscope may not meet its emissions requirements (EMI).

7. Remove the EMI gasket: If removing the EMI gasket for replacement, do thefollowing substeps.

a. Locate the EMI gasket to be removed in the diagram Front Cover, RearCover, Cabinet, EMI Gasket, and Cabinet Handle and Feet Removal,Figure 6–7.

b. Look for the point where the ends of the gasket touch in the channel atthe rear edge of the cabinet.

c. Use a pair of needle-nose pliers to pry up one of the ends of the gasket.

d. Grasp the EMI gasket, and gently pull it out of the its channel.



8. Reinstallation of cabinet and rear cover:

a. If the EMI gasket was removed, press the EMI gasket back into itsgroove at the rear edge of the cabinet. When installing, make sure theends of the gasket touch, but do not overlap. (Cut off excess length ifrequired to prevent overlap.)

b. See step 7 to reinstall the handle assembly if it was removed.

c. Do, in reverse order, steps 3 and 4 to reinstall the cabinet whileobserving the following precautions and requirements:

� Take care not to bind or snag the cabinet on internal cabling; redresscables an necessary.

� When sliding the cabinet onto the oscilloscope, be sure that the ridgearound the rear of the main chassis slides into the groove containingthe EMI gasket on the rear of the cabinet.

� Install the four screws at the rear panel and tighten to 8 inch-lbstorque before installing the single screw at the left side of thecabinet. Tighten this screw to 8 inch-lbs.

d. If installing a new rear panel, also do the following:

� Find the appropriate labels for your rear panel.

� Remove the covering from the back of the sticky-back labels, alignthem to the rear panel, and press firmly to install.

e. See the procedure Line Fuse and Line Cord to reinstall the line cord,which completes the oscilloscope reassembly.




a. Have handy a wooden spudger (Item 11).

b. Locate the modules to be removed in the locator diagram Cabinet andFront-Panel Mounted Modules, Figure 6–2 on page 6–16.

2. Orient the oscilloscope: Set the oscilloscope so its rear is down on the worksurface and its bottom is facing you.

3. Remove the front cover: If it is installed, grasp the front cover by its left andright edges and snap it off of the front of the oscilloscope. (When reinstall-ing, align and snap the cover back on.)

STOP. DO NOT touch the carbon contact points on the menu elastomer installedin the trim ring. Also, do not touch the contacts on the menu button flex circuitexposed when you remove the trim ring. You should wear clean cloth gloves thatare free of lint when handling the menu elastomer or when touching the menubutton flex circuit mounted on the front chassis.

Trim Ring: To remove, grasp its backedge and press up on its two tablocks. Flex the trim ring upward;then pull it forward. Repeat for thebottom edge of the trim ring.

MenuButton

(17)

TrimRing

TabLock

Menu Elastomer

Figure 6–8: Trim Ring, Menu Elastomer, and Menu Buttons Removal

Trim Ring, MenuElastomer, Menu Buttons,

and Front EMI Gaskets



4. Remove the trim ring:

a. Grasp the trim ring by its top edge and pry it up and lift it forward tosnap it off of the top front of the main chassis.

b. Repeat the process, prying on the bottom edge of the trim ring tocomplete its removal.

c. Lay the trim ring on its face on the work surface.

5. Remove the EMI gaskets: If servicing the front EMI gaskets, lift them out ofthe trim ring.

6. Remove the menu elastomer: If servicing the menu elastomer, lift it out ofthe trim ring.

7. Remove the menu buttons: If servicing the menu buttons, lift them out of thetrim ring.

8. Reinstallation:

a. If the menu buttons were removed, insert each button into its hole in thetrim ring.

b. If the menu elastomer was removed, align it over the menu button holesin the trim ring and press it in to install. Avoid touching the carboncontact points on the elastomer.

c. Without installing the EMI gaskets, align the trim ring to the front of thechassis and push it on to seat. Be sure that both pairs of flex locks, onepair each at the inside top and bottom of the trim ring, snap over theedge of the chassis.

d. Do the following subparts to install the EMI gaskets (see Figure 6–9):

� Install the front cover on the oscilloscope.

� Lay the scope so its front cover is on the work surface.

� Align an EMI gasket so it lays between any pair of adjacent flexlocks along the groove between the cabinet.

� Using a wood spudger, push the EMI gasket until it is firmly seatedat the bottom of the groove. It should not overlap either flex lock.

� Repeat the process just described to install the remaining threegaskets.



e. If the trim ring installed in substep c is a new trim ring, remove thecovering from the back of the sticky-back label, align it to the trim ring(see Figure 6–8 on page 6–30), and press firmly to install.

f. See the following procedures to install those modules removed by theaccess procedure:

� Front Cover, Rear Cover, Cabinet, Rear EMI Gasket, and CabinetHandle and Feet (page 6–26) to reinstall the cabinet and rear cover

� Line Fuse and Line Cord (page 6–25) to reinstall the line cord,which completes the oscilloscope reassembly

Spudger

EMI Gaskets (4)

Figure 6–9: EMI Gasket Removal and Installation



For this procedure you will need a screwdriver with a size T-15 Torx tip (items 1and 2) and a Pozidriv screwdriver (item 6).

1. If you have not already performed the Access Procedure on page 6–13 andremoved the modules as instructed, do so now.

2. Set the oscilloscope so its bottom is down, and its front is facing you.

Remove T-15Torx-drive

screw(see text)

J1

Removesecuring

screw(see text)

Figure 6–10: Disk Drive Removal

3. To remove the disk drive, perform the following steps using Figure 6–10 as aguide:

a. Lift up on the two locking tabs on J1 of the disk drive.

b. Remove the cable from the drive.

c. If present, remove the T-15 Torx-drive screw that clamps the drive in thechassis. When replacing the drive, do not reinstall this screw.

d. Remove the one or two screws securing the drive to the chassis.

e. Grasp the drive by its front edges and pull it out of the front panel tocomplete its removal.

Disk Drive



f. If present, remove the screw securing the spacer to the drive, and lift thespacer away from the drive to complete the removal.

4. To reinstall the disk drive, perform steps 3a–3f in reverse order.

1. Access the module: Be sure you have performed the Access Procedure onpage 6–13 and removed the modules as instructed.


a. Have handy a flat bladed screwdriver (Item 5).

b. Locate the modules to be removed in the locator diagram Cabinet andFront-Panel Mounted Modules, Figure 6–2 on page 6–16.

3. Orient the oscilloscope: Set the oscilloscope so its bottom is down on thework surface and its front is facing you.

4. Remove the front-panel assembly:

a. Insert a flat-bladed screwdriver (Item) into the slot at the front-right ofthe chassis. Push inwards to release the snap lock at the right side (seeFigure 6–11).

b. Lift the front-panel assembly out of the front of the main chassis untilyou can reach the interconnect cables connecting it to various othermodules.

c. Unplug the following cables from their jacks on the front-panelassembly:

� The menu flex circuit at J103

� The probe code flex circuit at J104

� The CPU-to-front panel cable at J101

� The backplane-to-front panel cable at J106

d. Finally, lift the front-panel assembly out of the front of the main chassisto complete the removal.

5. Remove the ESD shield: If replacing this shield, note how the small cutouton the shield is aligned to the snap lock at the lower-left corner of theassembly and reference for later replacement. Then pull the ESD shield offthe left edge of the front panel to remove. (The shield snaps on and off.)

A06 Front-PanelAssembly, ESD Shield,

and Menu Flex and ProbeCode Flex Circuits



ESDShield

Front PanelAssembly

Menu FlexCircuit

Probe CodeFlex Circuit

Press To ReleaseSnap Lock

Figure 6–11: A06 Front-Panel Assembly, ESD Shield, and Menu Flex and Probe Code Flex Circuits Removal

6. Remove the Probe Code Flex Circuit: If replacing or cleaning the probe codeflex circuit, remove the four T-15 Torx� screws, and lift the probe code flexcircuit away from the front of the main chassis.

STOP. Perform step 7 only if disassembling for cleaning and lubrication.(Components removed in step 7 are not field replaceable.) Otherwise, skip tostep 8 to continue this procedure.

7. Further disassembly of front-panel assembly: If the front panel or thefront-panel buttons are to be serviced, do the following substeps.

a. Remove the front-panel control knobs from the front-panel assemblyusing the method described in Front-Panel Knobs and Shafts onpage 6–23.

b. Release the five snap locks at the edge and center of the circuit board,and then pull the board away from the assembly until it unplugs fromJ405. See Figure 6–12.

c. Lift the circuit board away from the rest of the assembly.



d. Hand disassemble the front-panel-assembly components using Fig-ure 6–12 as a guide. Reverse the procedure to reassemble, using thesame Figure 6–12 as a guide.

ESD Shield

Front PanelBoard

Menu ButtonElastomer

Press latchto release.

Knobs andShafts

Flex the latches (3) downward torelease board. Then, rotate the

board and pull it down.

Figure 6–12: Disassembly of the Front-Panel Assembly

STOP. Perform step 8 only if replacing a failed or damaged menu flex circuitwith a fresh unit from the factory. (Removal of the circuit is likely to destroy it.)If such is not the case, skip to step 9 to continue this procedure.

8. Remove the menu flex circuit: Pull the flex circuit away from the front of themain chassis. (The flex circuit is held on by its sticky backing.)



9. Reinstallation:

a. If the menu flex circuit was removed in step 8, do the following subpartsto install a new circuit (reference Figure 6–11 on page 6–35):

� DO NOT touch the contacts on the menu flex circuit with your barefingers. You should wear clean cloth gloves that are free of lint wheninstalling the menu flex circuit on the front chassis.

� Wipe the front of the chassis using isopropyl alcohol and a clean,lint-free cloth. Let the chassis dry. (Some adhesive from the flexcircuit you removed will be left on the front of the chassis. This isnormal.)

� Find the score line in the adhesive backing and peel the backing offof the menu flex circuit.

� Carefully align the three holes on the menu flex circuit to the locatorstuds on the front of the main chassis. When the alignment iscorrect, press the flex circuit against the chassis so it adheres to thechassis.

� Clean the surface of the menu flex circuit just installed usingisopropyl alcohol and a clean, lint-free cloth.

b. See step 6 to install the probe code flex circuit if it was removed.

c. See step 5 to install the ESD shield if it was removed.

d. If the front-panel assembly was disassembled for cleaning in step 7,apply a thin coating of bearing grease (Dow Corning #1292) to the twoswitch patterns (circular patterns for the vertical scale rotary switches) onthe circuit board. Then reverse substeps 7a–7d to reassemble, usingFigure 6–12 as a guide.

e. Do in reverse order substeps 4a through 4d, reversing the procedureoutlined in each step. Be sure to dress the CPU-to-front-panel cable sothat the loop of extra cable length is in the front-panel cavity of thechassis, as shown in Figure 6–4.

f. See the following procedures to install those modules removed by theaccess procedure:






2. Assemble equipment and locate modules to be removed: Have handy ascrewdriver with a size T-15 Torx� tip (Items 1 and 2).

3. Orient the oscilloscope: Set the oscilloscope so its top is down on the worksurface and its front is facing you.

4. Remove the Attenuator Assembly:

a. Unplug the backplane to attenuator cable at J101.

b. Using Figure 6–13 as a guide, remove the four T-15 Torx� screwssecuring the attenuator assembly to the front of the chassis.

c. Lift the attenuator assembly away from the oscilloscope to complete itsremoval.

5. Reinstallation:

a. Perform in reverse order substeps 4a and 4c, reversing the removalinstructions in each substep to reinstall the assembly.

b. See the following procedures in the order listed to replace modulesremoved by the access procedure:

� A06 Front-Panel Assembly, ESD Shield, and Menu Flex and ProbeCode Flex Circuits on page 6–34

� Trim Ring, Menu Elastomer, Menu Buttons, and Front EMI Gasketson page 6–30



A05 Attenuator Assemblyand Shield



Mounting Screws (4)

Attenuator Shield

A05 Attenuator Assembly

Figure 6–13: A05 Attenuator Removal



NOTE. The display tube and the display-driver board are a single module andmust be removed and replaced as such. They are listed as a single module in theReplaceable Parts List.


2. Assemble equipment and locate modules to be removed: Have handy ascrewdriver with a size T-15 Torx� tip (Items 1 and 2). Locate the moduleto be removed in the locator diagram Internal Modules, Figure 6–3,page 6–19.

3. Orient the digitizing oscilloscope: Set the digitizing oscilloscope so itsbottom is down on the work surface, with its front facing you.

WARNING. Monitor assembly handling: Use care when handling a monitor. Ifyou break its display tube it may implode, scattering glass fragments with highvelocity and possibly injuring you. Wear protective clothing, including safetyglasses (preferably a full-face shield). Avoid striking the display tube with oragainst any object.

Monitor storage: Store the monitor with its display tube face down in aprotected location, placing it on a soft, nonabrasive surface to prevent scratch-ing the face plate.

4. Remove the monitor:

a. Take the precautions outlined in the WARNING above. Refer toFigure 6–14 while doing the following substeps.

b. Unplug the main cable at (J901), then rotate the digitizing oscilloscopeso its top is down on the work surface, with its bottom facing upwards.

c. Remove the three T-15 Torx� screws securing the monitor assembly tothe bottom of the main chassis. Return the digitizing oscilloscope to theorientation established in step 2.

WARNING. High-voltage is present on the anode lead. It is NOT necessary tounplug the anode from the monitor when removing or replacing the monitormodule; therefore, do not do so.

d. Remove the three T-15 Torx� screws securing the monitor assembly tothe top of the chassis. (See Figure 6–14 to locate the screws.)

A26 Monitor Assembly



e. Push up on the left top tab lock on the trim ring and pull the left cornerof the trim ring forward slightly. (The left top tab lock is shown inFigure 6–8 on page 6–30.)

f. Tilt the rear of the monitor assembly upward slightly. Slide the monitorassembly back in the main chassis until it stops (about 3�4 inch). Now liftit straight up out of the the top of the main chassis to complete theremoval.

g. While heeding the WARNING on monitor handling that immediatelyprecedes step 4 of this monitor removal procedure, store the monitorassembly in a protected location. Place it face down on a soft, nonabra-sive surface to prevent scratching the face plate.

5. Reinstallation:

a. Perform in reverse order 4a-4f, reversing the removal instructions ineach step and substep to reinstall the assembly. If the EMI clips on themonitor are replaced, be sure to center them in the notched area of thetop and bottom of the chassis.


� A06 Front-Panel Assembly, ESD Shield, and Menu Flex and ProbeCode Flex Circuits on page 6–34

� Trim Ring, Menu Elastomer, Menu Buttons, and Front EMI Gasketson page 6–30





A26 MonitorAssembly

MountingScrews (6)

MonitorFrame

EMI Clip

Figure 6–14: A26 Monitor Assembly Removal



1. Locate the modules to be removed: Find the modules to be removed in thelocator diagram Internal Modules, (Figure 6–3 on page 6–19) or in Figure6–4 on page 6–22.

2. Orient the digitizing oscilloscope: Set the digitizing oscilloscope so its leftside is down, with its front facing to the left of you.

3. Remove the board supports: Depress the snap lock at the bottom end of theboard support and tilt the support outwards to remove from the chassis.Repeat for the second and third board supports. See Figure 6–15.

4. Remove the D1 Bus: Grasp the D1 bus by its cable pull tab and pull tounplug it from J1 of the Display assembly. Then grasp the cable and pull tounplug it from J3 of the acquisition assembly and J2 of the DSP assembly.See Figure 6–15.

5. Remove the jumper board assembly: Grasp the jumper board assembly byopposite edges and pull out to unplug it from J102 of the attenuatorassembly and J9 of the acquisition assembly. Take care to pull the jumperboard straight out with a minimum of rocking motion. See Figure 6–15.

A08 Jumper Board

Board Support (3)

D1 Bus

Figure 6–15: A08 Jumper Board Assembly, D1 Bus, and Board Supports Removal

A08 Jumper BoardAssembly, D1 Bus, and

Board Supports



6. Reinstallation: Do steps 3 through 5, reversing instructions in each step toreinstall any module removed.


2. Assemble equipment and locate modules to be removed: Have handy ascrewdriver with a size T-15 Torx� tip (Items 1 and 2). Locate the modulesto be removed in the locator diagram Internal Modules, Figure 6–3,page 6–19.


4. Remove the CPU board: Using Figure 6–16 as a guide, perform thefollowing substeps:

a. Unplug the CPU to front panel cable from the CPU assembly at J101.

b. Lift up on the two locking tabs on J500 of the CPU assembly.

c. Remove the cable from the drive.

d. Remove the single T-15 Torx� screw from the bracket covering theunused rear-panel slot at the inside rear corner of the main chassis or thetwo screws from the bracket that secures the option assembly at theinside rear corner of the main chassis.

e. Remove the single T-15 Torx� screw from the bracket that secures theCPU assembly at the inside rear corner of the main chassis.

f. Working from the rear of the oscilloscope, remove the single T-15Torx� screw from the bracket that secures the CPU assembly to the rearof the main chassis.

g. Grasp the board by its edge and pull outward to unplug it from J3 of thebackplane assembly.

h. Slide the board part way out until you can reach the battery cable at J5.Unplug the battery cable.

i. Slide the board the rest of the way out of the main chassis to complete itsremoval.

A03 CPU Assembly



5. Reinstallation:

a. Perform in reverse order substeps 4a–4i, reversing the removal instruc-tions in each step and substep to reinstall the assembly. After plugging inthe CPU to front panel cable at J101, be sure to dress the cable so thatthe loop of extra cable is tucked behind the front-panel assembly, asshown in Figure 6–16. The cable should come from J101 on the CPUassembly and route directly through the chassis opening to the front-pa-nel cavity.


� A08 Jumper Board Assembly, D1 Bus, and Board Supports onpage 6–43 (board supports)



A03 CPU Assembly

MountingScrew (Short),CPU Assembly

MountingScrew, UnusedBoard Bracket

MountingScrew, CPUAssembly

Figure 6–16: A03 CPU Removal




2. Assemble equipment and locate modules to be removed: Have handy ascrewdriver with a size T-15 Torx� tip (Items 1 and 2). Locate the modulesto be removed in the locator diagram Internal Modules, Figure 6–3 onpage 6–19.


4. Remove the display board: Using Figure 6–17 as a guide, perform thefollowing substeps:

a. Unplug the monitor to display cable at J2.

b. Remove the single T-15 Torx� screw from the bracket that secures theCPU assembly at the inside rear corner of the main chassis.

c. Remove the single T-15 Torx� screw from the bracket that secures thedisplay assembly at the inside rear corner of the main chassis.

d. Working from the rear of the oscilloscope, remove the single T-15Torx� screw from the bracket that secures the display assembly to therear of the main chassis.

e. Grasp the board by its edge and pull outward to unplug it from J4 of thebackplane assembly to complete the removal.

5. Reinstallation:

a. Perform in reverse order substeps 4a-4e, reversing the removal instruc-tions in each substep to reinstall the assembly.


� A08 Jumper Board Assembly, D1 Bus, and Board Supports on page6–43 (board supports and D1 bus only)



A02 Display Assembly



A02 DisplayAssembly

MountingScrew (Short), DisplayAssembly

MountingScrew, DisplayAssembly

MountingScrew, CPUAssembly

D1 Bus (Removedby the Accessprocedure.)

Figure 6–17: A02 Display Assembly Removal



a. Have handy a screwdriver with a size T-15 Torx� tip (Items 1 and 2).

b. Locate the modules to be removed in the locator diagram InternalModules, Figure 6–3 on page 6–19.


4. Remove the DSP Assembly: Use Figure 6–18 as a guide perform thefollowing substeps:

a. Unplug the battery-backup cable at J5.

b. Remove the single T-15 Torx� screw from the bracket that secures thedisplay assembly at the inside rear corner of the main chassis.

c. Remove the single T-15 Torx� screw from the bracket that secures theDSP assembly at the inside rear corner of the main chassis.

A09 DSP Assembly



d. Working from the rear of the oscilloscope, remove the single T-15Torx� screw from the bracket that secures the DSP assembly to the rearof the main chassis.

A09 DSP Assembly

Mounting Screw(short), DSPAssembly

D1 Bus (Removedby the Accessprocedure.)

MountingScrew, DSPAssembly

MountingScrew, DisplayAssembly

Figure 6–18: A09 DSP Assembly Removal

e. Grasp the board by its edge and pull outward to unplug it from J5 of thebackplane assembly to complete the removal.

5. Reinstallation:

a. Perform in reverse order substeps 4a-4e, reversing the removal instruc-tions in each substep to reinstall the assembly.


� A08 Jumper Board Assembly, D1 Bus, and Board Supports on page6–43 (board supports and D1 bus only)







a. Have handy a screwdriver with a size T-15 Torx� tip (Items 1 and 2)and a flat-bladed screwdriver (Item 5).

b. Locate the modules to be removed in the locator diagram InternalModules, Figure 6–3 on page 6–19.

3. Orient the digitizing oscilloscope: Set the digitizing oscilloscope so its leftside is down, with its front facing to the left.

4. Remove the backplane assembly: Using Figure 6–19 as a guide, perform thefollowing substeps:

a. There may be board brackets, mounted on the rear panel, that correspondto unused board slots or options in the backplane assembly. For anybracket, do the following subparts to remove it:

� Remove the T-15 Torx� screw(s) that secure(s) the bracket at theinside rear corner of the main chassis.

� Working from the rear of the oscilloscope, remove the T-15 Torx�

screw(s) from the bracket(s) that secure(s) the bracket or assembly tothe rear of the main chassis.

b. Unplug the backplane to acquisition cable at J7 of the acquisitionassembly.

c. Unplug the backplane to attenuator cable at J101 of the attenuatorassembly.

d. Unplug the backplane to AUX power cable at J6 of the backplane.

e. Unplug the backplane to front panel cable at J8 of the backplaneassembly.

f. Unplug the backplane to low voltage power cable at J7 of the backplaneassembly.

A01 Backplane Assemblyand its Mount



A01 BackplaneAssembly

Lift latches (4)to release the board.

MountingScrew (5)

Figure 6–19: A01 Backplane Assembly and its Mount Removal

g. Remove the five T15 Torx� screws mounting the board to the chassis.

h. Turn the digitizing oscilloscope so its bottom is facing down on the worksurface. Leave its front facing to the left.

i. Find the flex lock nearest the front of the digitizing oscilloscope. Using aflat-bladed screwdriver, push the flex lock so it flexes enough to clearthe board.

j. While holding the flex lock, slightly pull up on the front corner of theboard nearest that retainer until the board clears that flex lock. Repeat forthe remaining three flex locks.



k. Once the board is clear of all four flex locks, grasp the board by the edgenear those flex locks and rotate that edge upwards slightly and pull theboard out of its retainer slot at its opposite edge.

l. As you lift the backplane assembly out of the chassis, guide thebackplane to attenuator and backplane to acquisition cables up throughtheir slots in the bottom of the chassis.

m. Lift the assembly all of the way out of the chassis to complete theremoval.

5. Reinstallation:

a. Perform in reverse order substeps 4a-4m reversing the removalinstructions in each substep to reinstall the assembly. Observe thefollowing precautions as you do the substeps:

� Be sure to guide the backplane to attenuator and backplane toacquisition cables up through their slots in the bottom of the chassiswhen doing step 4l.

� Be sure to align the board to the retainer slot when doing step 4k.

� Seat the board until the four retainers snap over the edge of thebackplane assembly when doing substep 4j.


� A08 Jumper Board Assembly, D1 Bus, and Board Supports on page6–43 (board supports and D1 bus only).

� Front Cover, Rear Cover, Cabinet, Rear EMI Gasket, and CabinetHandle and Feet (page 6–26) to reinstall the cabinet and rear cover.

� Line Fuse and Line Cord (page 6–25) to reinstall the line cord,which completes the oscilloscope reassembly.



CAUTION. The batteries used in this oscilloscope can present a fire or chemicalburn hazard if mistreated. Do not recharge, rapidly discharge, disassemble, heatabove 100� C, or incinerate.

Replace batteries with the part number listed in the Replaceable Parts List only.Use of another battery presents a risk of fire or explosion.

Dispose of used batteries promptly. Small quantities of used batteries may bedisposed of in normal refuse. Keep away from children. Do not disassemble, anddo not dispose of in fire.

STOP. Disconnection of the batteries from their plugs results in the loss of allsaved front panel setups and saved waveforms. Adjustment constants, storedinternally when the oscilloscope is adjusted, are not lost.

1. Assemble equipment and locate modules to be removed: Locate the back-upbattery to be removed in the locator diagram Internal Modules, Figure 6–3,page 6–19.

2. Orient the digitizing oscilloscope: Set the digitizing oscilloscope so its top isdown on the work surface, with its right side facing you.

3. Remove back-up battery 1: Unplug the back-up battery cable at J5 of theCPU assembly. Then pull the battery out of its clamp near the front of thechassis to remove.

4. Remove back-up battery 2: Unplug the back-up battery cable at J5 of theDSP assembly. Then pull the battery out of its clamp near the front of thechassis to remove.

5. Remove the battery retaining clip: If replacement of the battery clip isnecessary, remove the T15 Torx� screw mounting the clip to the chassis.

Back-Up Batteries



To J5 of theA09 DSPAssembly

To J5 of the A03 CPUAssembly

Figure 6–20: Battery Removal

6. Reinstallation:

a. If the battery retaining clip(s) was removed, do step 5, reversing theremoval instructions to reinstall the each battery clip.

b. Do steps 3 and 4, reversing the removal instructions to reinstall the eachbattery.

c. See the following procedures in the order listed to replace modulesremoved by the access procedure:






2. Locate modules to be removed:

a. Have handy a screwdriver with a size T-15 Torx� tip (Items 1 and 2)and a pair of duck bill pliers (Item 8).

b. Find the low voltage power supply and, if it is to be removed, thepower-supply mount in the locator diagram Internal Modules, Fig-ure 6–3 on page 6–19.

3. Orient the digitizing oscilloscope: Set the digitizing oscilloscope so itsbottom is down on the work surface and its front is facing to the right.

CAUTION. When releasing the low voltage power supply from its mount, takecare not to push on the board components. Rather, push on the board edge whenperforming the following step and its substeps.

4. Remove the low voltage power supply:

a. Unplug the cable coming from the backplane assembly at J2.

b. Unplug the cable coming from the AUX power supply at J1.

c. Working through the opening created when the fan was removed (AccessProcedure), remove the T-15 Torx� screw at the center of the powersupply board.

d. Using a pair of duck-bill pliers, squeeze to release each of the four flexlocks at the top edge of the low voltage power supply assembly.

e. Once released, tilt the board out away from the flex locks, and unplugthe AC power cable where it connects to the cable from the low voltagepower supply.

f. Lift the low voltage power supply assembly out of the chassis tocomplete its removal.

A25 Low Voltage PowerSupply and its Mount



To AuxPowerSupply

MountingScrew (1)

Use pliers to releaseboard latches.

Press release latches inwhile pulling up on mount.

Figure 6–21: A25 Low Voltage Power Supply Removal

STOP. DO NOT do step 5 unless servicing a broken power supply mount orremoving that mount for cleaning.

5. Remove the power-supply mount:

a. Place the digitizing oscilloscope so its left side is down with its topfacing you.

b. Depress the two retainer locks and slide the power-supply mounttowards the top of the digitizing oscilloscope to unlock from the chassis.



c. Lift the power-supply mount out of the chassis to complete the removal.When reinstalling the power-supply mount, be sure to press it flushagainst the chassis before sliding it towards the bottom of the chassis to lock.

6. Reinstallation:

a. If the power supply mount was removed, do the following subparts:

� Do in reverse order substeps 5a–5c, reversing the removal instruc-tions in each substep to reinstall the assembly.

� See A02 Display Assembly, on page 6–46, to reinstall that assembly.

� See A09 DSP Assembly, on page 6–47, to reinstall that assembly.

� See A03 CPU Assembly, on page 6–44, to reinstall that assembly.

� See A08 Jumper Board Assembly, D1 Bus, and Board Supports onpage 6–43 to reinstall the board supports and D1 bus only.

b. Perform in reverse order substeps 4a-4f, reversing the removal instruc-tions in each substep to reinstall the assembly. Be sure to seat the boarduntil all of the four flex locks are locked.

c. See the following procedures to replace the modules removed by theaccess procedure.






2. Assemble equipment and locate modules to be removed: Locate the modulesto be removed in the locator diagram Internal Modules, Figure 6–3,page 6–19.

3. Orient the digitizing oscilloscope: Set the digitizing oscilloscope so that itsbottom is down and its rear is facing you.

4. Remove the fan:

a. Unplug the power cable for the fan from J3 on the Auxiliary PowerSupply.

b. Release the two flex locks securing the top of the fan to the fan mount,then lift the fan out from the top of the chassis.

c. When reinstalling the fan, be sure the two locks snap into place to securethe fan.

STOP. DO NOT do step 5 unless servicing a broken fan mount or removing thatmount for cleaning.

5. Remove the fan mount:

a. Rotate the digitizing oscilloscope so the side that houses the fan mountis facing upwards.

b. Depress the two flex locks to release them (see Figure 6-21).

c. While holding the flex locks released, slide the fan mount so its fourretainer lugs slide from their small retainer holes in the chassis into theirlarge release holes.

d. Move the fan mount inward so its retainer lugs are out of the largeretainer holes and lift it out of the chassis to remove.

Fan and Fan Mount



Lift flexlocks. Fan

FanMount

Move fan mountinward and lift.

Left Rear of Scope

Press flexlocks.

RetainerLugs (4)

Releasing the Fan Mount Lugs

Figure 6–22: Fan and Fan Mount Removal

6. Reinstallation:

a. If the fan mount was removed, perform in reverse order substeps 5a–5dreversing the removal instructions in each substep to reinstall the fanmount. Be sure to seat the fan mount so its two flex locks snap to secureit on the chassis.

b. Do in reverse order substeps 4a–4c, to reinstall the fan.

c. See the following procedures to replace the modules removed by theaccess procedure:






2. Assemble equipment and locate modules to be removed: Have handy ascrewdriver with a size T-15 Torx� tip (Items 1 and 2). Locate the line filterin the locator diagram Internal Modules, Figure 6–3, page 6–19.

3. Orient the digitizing oscilloscope: Set the digitizing oscilloscope so itsbottom is down on the work surface and its rear is facing you.

4. Remove the line filter: Refer to Figure 6–23 when doing the followingsubsteps.

a. Unplug the three connectors at the line filter.

b. Remove the two screws mounting the line filter to the chassis. Pull thefilter out through the rear of the chassis to complete the removal.

Figure 6–23: Line Filter Removal

Line Filter



5. Reinstallation:

WARNING. When reconnecting the auxiliary power supply to the line filter, besure to connect the neutral side of the line filter to the black-striped lead and theload side to the white-striped lead.

It is not necessary to disconnect the earth ground from the chassis lug that it isbolted to. If, however, you have done so, be sure to install the earth lead (and itsnut) from the line filter before installing the earth lead (and its nut) from the lowvoltage power supply.

a. Do in reverse order substeps 4a–4b, reversing the removal instructions ineach substep to reinstall the assembly.

b. See the following procedures to replace the modules removed by theaccess procedure:







a. Have handy a screwdriver with a size T-15 Torx� tip (Items 1 and 2)and a 5�16 inch nut-driver (Item 9).

b. Locate the auxiliary power supply in the locator diagram InternalModules, Figure 6–3 on page 6–19.

3. Orient the digitizing oscilloscope: Set the digitizing oscilloscope so itsbottom is down on the work surface and its rear is facing you.

4. Remove the auxiliary power supply: Reference Figure 6–24 while doing thefollowing substeps.

a. Unplug the monitor-power cable at J4, the fan-power cable at J3, thecable from the backplane assembly at J7, and the cable from the lowvoltage power supply assembly at J1 of the low voltage power supply assembly.

b. Using a 5�16 inch nut driver remove the nut(s) that secure the cable fromthe lug and remove it. When replacing the cables on the ground lug,install the cable from the line filter last.

c. Now, release and disconnect the remote-power cable where it joins thecable from the low voltage power supply assembly.

d. Unplug the two connectors at the line filter.

WARNING. When reconnecting the auxiliary power supply assembly to the linefilter, be sure to connect the neutral side of the line filter to the black-stripedlead and the load side to the white-striped lead.

e. Remove the two T-15 Torx� screws mounting the auxiliary powersupply assembly to the chassis. Then, pull up on the board to release itfrom the two retainers. Lift the board out of the chassis to complete the removal.

A07 Auxiliary PowerSupply



Figure 6–24: Auxiliary Power Supply Removal

5. Reinstallation:

a. Perform in reverse order substeps 4a–4e reversing the removal instruc-tions in each substep to reinstall the assembly. Be sure to seat the boarduntil the two mounting posts snap locked on the assembly whenreinstalling.




� A08 Jumper Board Assembly, D1 Bus, and Board Supports onpage 6–43 (board supports and D1 bus only).

� A06 Front-Panel Assembly, ESD Shield, and Menu Flex and ProbeCode Flex Circuits on page 6–34.

� Trim Ring, Menu Elastomer, Menu Buttons, and Front EMI Gasketson page 6–30.




2. Assemble equipment and locate modules to be removed: Have handy ascrewdriver with a size T-15 Torx� tip (Items 1 and 2). Locate the acquisi-tion assembly in the locator diagram Internal Modules, Figure 6–3 onpage 6–19.

3. Orient the digitizing oscilloscope: Set the digitizing oscilloscope so itsbottom is up, with its front facing you.

4. Remove the acquisition assembly: Use Figure 6–25 as a guide.

a. Unplug the cable from the backplane assembly from J7 of the acquisitionassembly.

b. Unsolder the wire from the AUX TRIGGER/EXT CLOCK BNC.

c. Remove the six screws securing the acquisition assembly to the bottomof the chassis, and lift out the acquisition assembly to complete itsremoval.

A04 Acquisition Assembly



Mounting Screws (6)

A04 Acquisition Board

Figure 6–25: A04 Acquisition Board Removal

5. Reinstallation:

a. Perform in reverse order substeps 4a-4c reversing the removal instruc-tions in each substep to reinstall the assembly.


� A08 Jumper Board Assembly, D1 Bus, and Board Supports on page6–43 to install the jumper board and D1 bus only





1. Remove the main chassis: Since the removal of the main chassis requires theremoval of virtually all modules, perform the procedure Disassembly forCleaning that follows.

2. Reinstallation: See reinstallation instructions in Disassembly for Cleaning.

Disassembly for CleaningThis procedure is for disassembly of the digitizing oscilloscope into its individu-al modules so they can be cleaned. Read the cleaning instructions in Inspectionand Cleaning on page 6–4 before disassembling this oscilloscope.


a. Have handy a screwdriver with a size T-15 Torx� tip (Items 1 and 2), aT-20 Torx� tip (Item 3), a flat-bladed screwdriver (Item 5), a pair ofangle-tip tweezers (Item 10), duck bill pliers (Item 8), flat bladedspudger (Item 11), and a soldering iron (Item 12).

b. Familiarize yourself with the modules illustrated in Figures 6–2, 6–3,and 6–4 on pages 6–16, 6–19, and 6–22 respectively.

2. Remove all modules: Do, in the order listed the following procedures. Theyare found under Procedures for Module Removal and Installation whichstarts on page 6–23.

a. Line Fuse and Line Cord (page 6–25)

b. Front Cover, Rear Cover, Cabinet, Rear EMI Gasket, and CabinetHandle and Feet (page 6–26)

c. Disk Drive (page 6–33)

d. Trim Ring, Menu Elastomer, Menu Buttons, and Front EMI Gaskets(page 6–30)

e. A06 Front-Panel Assembly, ESD Shield, and Menu Flex and Probe CodeFlex Circuits (page 6–34)

f. Fan and Fan Mount (page 6–57)

g. A25 Low Voltage Power Supply and its Mount (page 6–54)

h. A26 Monitor Assembly (page 6–40)

i. A07 Auxiliary Power Supply (page 6–61)

j. Line Filter (page 6–59)

k. A08 Jumper Board Assembly, D1 Bus, and Board Supports (page 6–43)

Main Chassis



l. A03 CPU Assembly (page 6–44)

m. A02 Display Assembly (page 6–46)

n. A09 DSP Assembly (page 6–47)

o. A01 Backplane Assembly and its Mount (page 6–49)

p. Back-up Batteries (page 6–52)

q. A05 Attenuator Assembly and Shield (page 6–38)

r. A04 Acquisition Assembly (page 6–63)

3. Reassembly: Do substeps a–r in the order listed. Observe the followinginstructions as you do them:

� The procedures called out in the substeps that follow reinstall all themodules. When doing these procedures, do their steps in reverse order.

� When reinstalling the modules, ignore any instructions that require connect-ing a cable or bus to a module that you have not yet installed. You will makethe necessary connections when you install the missing module later.

� Ignore any instructions to do the Access Procedure. The access procedure isonly used when removing individual modules for servicing, not when doinga disassembly/reassembly for cleaning.

� Ignore any instructions directing you to see other procedures to reinstallmodules removed by the access procedure. The substeps that follow directyou to the procedures needed to reinstall all of the modules.

a. A04 Acquisition Assembly (page 6–63)

b. A05 Attenuator Assembly and Shield (page 6–38)

c. Back-up Batteries (page 6–52)

d. A01 Backplane Assembly and its Mount (page 6–49)

e. A09 DSP Assembly (page 6–47)

f. A02 Display Assembly (page 6–46)

g. A03 CPU Assembly (page 6–44)

h. Line Fuse and Line Cord (page 6–25)

i. A08 Jumper Board Assembly, D1 Bus, and Board Supports (page 6–43)

j. Line Filter (page 6–59)

k. A07 Auxiliary Power Supply (page 6–61)



l. A26 Monitor Assembly (page 6–40)

m. A25 Low Voltage Power Supply and its Mount (page 6–54)

n. Fan and Fan Mount (page 6–57)

o. Trim Ring, Menu Elastomer, Menu Buttons, and Front EMI Gaskets(page 6–30)

p. Disk Drive (page 6–33)

q. A06 Front-Panel Assembly, ESD Shield, and Menu Flex and Probe CodeFlex Circuits (page 6–34)

r. Front Cover, Rear Cover, Cabinet, Rear EMI Gasket, and CabinetHandle and Feet (page 6–26)

s. Line Fuse and Line Cord (page 6–25)




Troubleshooting

This section contains information and procedures designed to help you isolatefaulty modules in the oscilloscope. If a module needs to be replaced, follow theRemoval and Installation Procedures located on page 6–9. If servicing aTDS 430A, follow the procedures for the TDS 460A, but ignore all references toCH 3 and CH 4.

CAUTION. This oscilloscope operates over several ranges of line voltage (seeSource Voltage and Frequency on page 1–18 of Chapter 1, Specification). Beforestepping the line voltage from one range to a higher range, set the principalpower switch (rear panel) to its OFF position. Failure to do so can damage theoscilloscope.

DiagnosticsThe oscilloscope has two levels of internal diagnostics that focus on verifying,adjusting, and, if need be, isolating faulty modules.

Both levels of internal diagnostics report any bad modules or interfaces. If thediagnostics do find a bad module or interface, use the troubleshooting proceduresin this section to determine which module needs to be replaced.

The two levels of diagnostics are the short confidence set and an extended setthat tests the oscilloscope circuitry in-depth and takes more time. At power–on,the oscilloscope automatically executes the short set. The extended set isoptional and is executed by using the following procedure:

Prerequisites: Power up the oscilloscope and allow a 20 minute warm-up beforedoing this procedure.

1. Display the System diagnostics menu:

a. Press SHIFT; then press UTILITY .

b. Repeatedly press the main-menu button System until Diag/Err ishighlighted in the menu that pops up.

c. Repeatedly press the main-menu button Area until All is highlighted inthe menu that pops up.

2. Run the System Diagnostics: Press the main-menu button Execute; thenpress the side-menu button OK Confirm Run Test.

Troubleshooting


3. Wait: The internal diagnostics do an exhaustive verification of properoscilloscope function. This verification takes about two minutes. Whenfinished, the oscilloscope displays a report of any bad modules or interfaces.

Firmware UpdatesFirmware updates are easy to do. Simply install the firmware disks on your PCand follow the instructions in the README file located on the first disk. Thefirmware update kit is listed as an optional accessory in Chapter 10.

NOTE. You must set both switches of the Protection switch to the unprotectedposition before updating the firmware. Figure 6–26 shows how to set the switch.After loading the firmware, be sure you set both switches back to the protectedposition and cycle power.

If you want to order a firmware update, see Optional Accessories in Chapter 10Mechanical Parts List for the part number.

Flip both switch levers towardthe board (closed) to enable

updating of firmware.

Figure 6–26: Accessing the Protection Switch

Troubleshooting


Troubleshooting EquipmentEquipment listed in Tables 4–1, 5–3, 6–4, and 6–8 of this manual, or equivalentequipment, may be useful while troubleshooting this oscilloscope. Constructionof and set-up of other troubleshooting equipment are also listed in this section.

Table 6–8: Troubleshooting Test Equipment, Fixtures, and Supplies

Item Number andDescription Minimum Requirements Example Purpose

1. Console Port Tektronix part number174-2613-00

Tektronix part number174–2613–00 (see Figure 6–27on page 6–73)

Troubleshooting using theConsole Port

2. Computer IBM� PC compatible Troubleshooting using theConsole Port

3. Extension cable Console port to computerconnection

Troubleshooting using theConsole Port

4. Telecommunication software

RS-232, 9600 baud Cross Talk� Troubleshooting using theConsole Port

5. Oscilloscope 200 MHz (for the TDS 420A) or400 MHz (for the TDS 430Aand TDS 460A) digitizing oscil-loscope

TEKTRONIX TDS 430A,TDS 420A, or TDS 460A

General troubleshooting

The console port allows you to see detailed diagnostic messages when faults inthe oscilloscope prevent display of the normal diagnostics. Use this procedure toset up the console port:

NOTE. You may need a DB-9 to DB-25 adaptor, null modem adaptor, genderchanger adaptor, and an extension cable to connect the console port to yourpersonal computer (see Figure 6–27 on page 6–27). Using Table 6–9 as a guideyou can wire a cable to take the place of a DB9 to DB25 adaptor, null modemadaptor, gender changer, and an extension cable.

1. Equipment required: Console port (Item 1), a personal computer orterminal (Item 2), and telecommunication (terminal) software (Item 4) forthe personal computer. Your personal computer may also require a DB-9 toDB-25 adaptor, null modem adaptor, gender changer adaptor, and anextension cable to connect the console port to your personal computer (seeFigure 6–27 on page 6–73).

2. Prerequisites: Power off the oscilloscope.

Console Port Set Up

Troubleshooting


3. Accessing J3: Using the Front Cover, Rear Cover, Cabinet, Rear EMIGasket, and Cabinet Handle and Feet disassembly procedure, remove thecabinet.

Table 6–9: Connections for a 9 to 25 Pin Null Modem Cable

DB-9 Signals DB-9 Pin DB-25 Pin DB-25 Signals

DCD 1 20 DTR

RD 2 2 TD

TD 3 3 RD

DTR 4 6 and 8 DSR and DCD

SG 5 7 SG

DSR 6 20 DTR

RTS 7 5 CTS

CTS 8 4 RTS

Unused (RI) 9 – All Others Unused

4. Connecting the equipment: Attach the console-port cable to J3 on theA03 CPU module (see Figure 6–27) and, using an extender cable oradaptors, to the RS-232 serial port of your personal computer (or RS-232terminal).

5. Configure the personal computer:

a. Load the software: Load telecommunication (terminal) software intoyour personal computer.

b. Select the software port: Configure the telecommunication software sothat it accesses the serial port that you connected to the console port(Com1 or Com2).

c. Configure port parameters: Set the telecommunication software (orterminal) parameters:

� Baud Rate 9600

� Parity None

� Data Bits 8

� Stop Bits 1

� Duplex Full

� Protocol None

Troubleshooting


� Terminal ANSI

d. Select terminal mode: After configuring the software parameters, switchthe software to terminal mode.

6. Use the console port: Power up the oscilloscope. Diagnostic messages areechoed to the personal computer display.

Console PortTektronix

part number174-2613-00

Extension Cable

Figure 6–27: Console Port Connections

Troubleshooting


Figure 6–28: Primary Troubleshooting Procedure

Power off and remove the coverusing the Front Cover, RearCover, Cabinet, Rear EMI

Gasket, and Cabinet Handle and Feet removal procedure. Checkall the cables coming out of theLow Voltage Power Supply and

the cabling between modules. Besure every cable is attached

securely.

Replace theA03 CPU module.�

NOTE: Thereplacement module

will not havefirmware loaded.

See 6–70 for detailson firmware updates.

Perform the Consoletroubleshooting procedure.�

Doesthe oscilloscope

power on and all thediagnostics

pass?

Yes

No

Yes

No

No

Yes

Press on the principal powerswitch on the back of the

oscilloscope.

Can you hearthe fan

whirling?

Press the ON/STBY button.Can you hear the fan

now?

When the oscilloscope

powers on, do the front panel lights come on and

then go off a short time later?

Yes

No

Perform the Processor/Front Panel

troubleshooting procedure.

Does the system power

on now?

Yes

Doesthe display seem to

be workingat all?

No

DoesDS1 flash .�,

then display the sequence of hex numbers

pausing to flash .�?

Set both switches of S2 on theA03 CPU module to their open

positions. Set all switches of S1 backto the closed position and cycle

power.�

Is the display readable

and stable?

Yes

No

No

Yes

Yes

No

Perform the Monitortroubleshooting procedure.�

There is somethingwrong with the

ON/STBY button.Perform the Backplane

troubleshootingprocedure.

No

Yes

Does DS1 first flash .�, then display

a sequence of hexnumbers from 1–e with

no period precedingthem?

Perform the Low VoltagePower Supply


Perform the Module Isolationtroubleshooting procedure.

Doesthe oscilloscope

respond correctly whenthe front panel buttons

are pushed?

Yes

No

Perform the Processor/Front Panel


Power on again and

observe LED DS1. Does it only

display .�?

Yes Replace the A03 CPUmodule.�

Is there 5.1 V

on P1 pin 3 (seeFigure 6–29)?

Yes

No Perform the Low Voltage PowerSupply troubleshooting

procedure.�

No

1Note: Set all the switches of S1 back to the closed position and cycle power before performing another procedure.

Done.

Do you have a console

port?

No

Yes

Are both switches of S2in the open position?

No

Yes

Power off the oscilloscopeand remove its cabinet usingthe Front Cover, Rear Cover,Cabinet, Rear EMI Gasket,

and Cabinet Handle and Feet removal procedure. On the A03 CPU module

set the eighth switch of S1to the open position.

Troubleshooting


P1

Pin 3 Pin 1 Pin 32

Figure 6–29: A03 CPU Board Connector P1

Troubleshooting


Figure 6–30: Module Isolation Troubleshooting Procedure

In Table 6–10 on page 6–77, find the row containing the first failure reported on the display. Select modules fromthe table row in numeric order starting with number 1. The table uses abbreviations for the modules:

Cpu = A03 CPU D1 Cable = D1 Bus cableDsp = A09 DSP Acq Cable = Backplane to Acquisition cableDsy = A02 Display Attn Cable = Backplane to Attenuator cableAttn = A05 Attenuator Jumper Board = A08 JumperAcq = A04 Acquisition Front Panel cables = Backplane to Front Panel and CPU to Front PanelBackplane = A01 Backplane Fp = A06 Front Panel

Replace the module. Run allextended diagnostics.

Yes

No

Done.

Yes

No

No

Yes

This procedure assumes thatthe oscilloscope is up and

running and you can read thedisplay.

Does the display report

any errors?

Select the extended diagnostics menuand run all the tests (for additional

diagnostics information, seeDiagnostics on page 6–69).

Are any failuresreported?

The oscilloscope is ok.

Yes

No

Is the selected module

the A05 Attenuator,A04 Acquisition, or the

A08 Jumper board?

Using thetroubleshooting

procedures did you finda faulty

module?

Perform the Attenuator/Acquisition andAcquisition and Attenuator Power

troubleshooting procedures.

Is the selected module the

A06 Front Panel board?


procedures did you find a faulty

module?

Perform the Processor/Front Paneltroubleshooting procedure.

No

Yes

Yes

NoIs the

selected modulethe A01 Backplane?

Yes

No

Perform the Backplanetroubleshooting procedure.


procedure did you finda faulty module?

No

Yes

Done.Done.

Does thedisplay reportany errors?

Select the next module fromTable 6–10.

No

Yes

Done.

Select the next module fromTable 6–10.

Troubleshooting


Table 6–10: Diagnostic Failure Priority Lists

Module Cpu Dsp Dsy Attn AcqBack-plane

D1Cable

AcqCable

AttnCable

Attn/AcqJumperBoard

FrontPanelCables Fp

Cpu 1 2 3 4 5

Cal Initialization 1

Cpu/Dsp or AT bus 2 1 3 4

Dsp 1 2 4 3

Cpu/Dsp/Dsy or D1 bus 3 1 4 2

Cpu/Dsp/Dsy or AT bus 1 2 3 4

Dsy 3 1 4 2

Cpu/Attn or I2C bus 2 1 4 3 3

Attn 1 3 2

Cpu/Acq, D1/I2C bus 5 4 1 2 3

Acq 3 1 4 5 2

Acq/Attn 2 3 4 1

Fp/Cpu 3 2 1

Troubleshooting


Figure 6–31: Low Voltage Power Supply Troubleshooting Procedure

Yes

No

Yes

No

No

Yes

It is not an A25 Low Voltage PowerSupply problem. Perform the

Backplane troubleshooting procedure.

Use this procedure totroubleshoot the Low

Voltage Power Supply.

Is the principal power switch

(S1) in the on (in) position?

Press principal powerswitch S1 to the on (in)

position.

Is line fuseF1 ok?

Press principal powerswitch S1 to the off (out)

position. Replace thefuse. Press principal

power switch S1 to theon (in) position.

Does the fuseblow?

Disconnect the cable from J1.Replace the fuse.

Yes

No

Replace the A07 AuxiliaryPower board and the cables

going to it.

Replace the A25 Low VoltagePower Supply.

Replace the A25 LowVoltage Power Supply.

Is there 90–250 VAC at J1 pins 1

and 3 on the A25 LowVoltage Power Supply?

Is there90–250 VAC at the

line filter?

Replace theA07 Auxiliary Power

board.

No

Yes

Is there power

at the line cordand outlet?

Replace the line filter.

Fix the power problem.

Are all secondary voltages

within specification (seeTable 6–11

and Figure 6–33)?

Replace either theA01 Backplane or the

A03 CPU boards.

Press principal power switch S1 to the off (out)position. Disconnect the cable (P2) to the

A01 Backplane. Connect a minimum 1 A load to the +5 V supply. Press principal power

switch S1 to the on (in) position.

Perform the Power Supply Overloadtroubleshooting procedure.

Yes

No

Does the fuse blowagain?

Yes

No

No

Yes

Yes

No

YesAre the

secondary voltages withinspecification (see Table 6–11 and Figure 6–33)?

No

Press principal power switch S1 to the off(out) position.

Disconnect the REMOTE_S/D cable (J4)from the A07 Auxiliary Power board (J4connects the A07 Auxiliary Power and

A25 Low Voltage Power Supply boards).

WARNING: The power supplies willcome up as soon as principal powerswitch S1 is in the on (in) position.

Press principal power switch S1 to the on(in) position.

Are the secondary voltages

within specification (see Table 6–11 and Figure 6–33)?

Troubleshooting


Table 6–11: Normal Output Voltage

Supply J2 Pin Minimum Output Maximum Output

+5.1 V 20 +5.05 V +5.15 V

+15 V 8 +14.85 V +15.15 V

–6.4 V 6 –6.35 V –6.45 V

–15 V 2 –14.85 V –15.15 V

Troubleshooting


Figure 6–32: Power Supply Overload Troubleshooting Procedure

Yes

No

Yes

No

No

Yes

Use this procedure totroubleshoot a power supply

overload problem.

CAUTION: Turn the oscilloscopepower off before removing a board or

disconnecting a cable.

Remove loads one at a time (removeeach plug-in circuit board and

disconnect cables from theA01 Backplane).

Does the supply work

ok when a specificboard or cable is

removed?

Replace board or cable thathas the fault.

Does the supply work ok

when all boards andcables are removed?

Replace theA01 Backplane.

No

Yes

Does the

supply work ok when the load is

reduced by removing or disconnecting one or more boards

or cables, but not due to an overload or short on

a specific board or cable?


Check the current drawn from thepower supply secondary.

Does the current

drawn exceed thespecification shown in

Table 6–12?

Check and repair the circuit.


Troubleshooting


Table 6–12: Power Supply Maximum Current

Supply J2 Pins Maximum Current

+5.1 V 16–20 15 A

+15 V 8 and 9 3.5 A

–6.4 V 6 and 7 5.5 A

–15 V 1 and 2 0.75 A

A25 Low Voltage Power Supply

J2Pin 1

Figure 6–33: A25 Low Voltage Power Supply Module (Right Side)

Troubleshooting


Figure 6–34: Monitor Troubleshooting Procedure

Replace the cable.

Replace the cable.

Replace the D1 Buscable, A03 CPU,

A09 DSP, orA01 Backplane Assembly.

No

Yes

Replace the A02 Displaymodule.

Isthe display

legible but thehorizontal and/or

vertical sync do notlook ok?

Dopins 2 and 4 of J440

have signals similar toFigure 6–35?

No

Yes Replace theA26 MonitorAssembly.

Power the oscilloscope off anddisconnect the cable from J440 on theA26 Monitor module (see Figure 6–37)

then power back on.

Ispin 1 of the cable at

+15 V?

No

Yes

On the A07 Auxiliary Power moduleprobe J7 and J4.



Does pin 7 of the cable have a video

signal with the same levels asFigure 6–36?

No

Yes

No

Yes

This procedure helps you determine whether the

A26 Monitor or the A02 Displaymodule is bad.

Is J7 pin 1 at +15 V (see

Figure 6–38)?

Is J4 pin 1 at +15 V (see

Figure 6–38)?

Replace the A07 Auxiliary Powermodule.

No

YesReplace the cable.

DoesJ2 pin 7

on the A02 Display module (seeFigure 6–39) have a video signal

with the same levels asFigure 6–36?

Yes

No

Dopins 2 and 4

of J2 (see Figure 6–39have signals similar to

Figure 6–35?

Yes

No

Power the oscilloscope off anddisconnect the cable from J440 on theA26 Monitor module (see Figure 6–37)

then power back on.

No

YesDo pins 2

and 4 of the cablehave signals similar to

Figure 6–35?

Is the problem

fixed?

Yes

No

Done.

Troubleshooting


J2 pin 2 (Horizontal Sync)31.75 kHz Rate

J2 pin 4 (Vertical Sync)60 Hz Rate

Figure 6–35: Horizontal and Vertical Sync Signals

J2 pin 7 (Video)

Blanking Level

White Level

Black Level

Figure 6–36: A Video Signal with White, Black, and Blanking Levels

Troubleshooting


J440

Figure 6–37: A26 Monitor Connector J440

J7Pin 1

J4Pin 1

Figure 6–38: A07 Auxiliary Power Connectors J4 and J7

Troubleshooting


J2Pin 1

Figure 6–39: A02 Display Connector J2

Troubleshooting


Yes

No

No

Yes

Securely install orreplace the front panel

cables.

Use this procedure todetermine if the A03 CPU or

the A06 Front Panel module isbad.

Do all of the front panel LEDs

turn on and then turn off ashort

time later?

Turn on the principle POWERswitch.

Press the ON/STBYbutton.

Do the front panelLEDs turn on at

all?

No

Yes

No

Yes

Are the correct voltagesat J101 and J106(see Figure 6–41and Table 6–13?

Replace theA06 Front Panel

module.

No

Yes

Does one front panel LED

turn on and then turn off, followed bythe next LED until all LEDs have

turned on and then turned off?

The A06 Front Panelboard is ok.

Are all front panel cables

securely installed in theirsockets and are the

cables ok?

Replace theA03 CPU board.

No

Yes

Do the front

panel LEDs turn on ashort time later and

then turn off?

Figure 6–40: Processor/Front Panel Troubleshooting Procedure

Troubleshooting


J106 Pin 1

J107 Pin 1

Figure 6–41: A06 Front Panel Board Power Connectors J101 and J106

Table 6–13: Front Panel Connector Voltages

Connector Pin Nominal Voltage

J101 Pins 2 and 4 5.1 V

J106 Pin 1 15 V

J106 Pin 2 5.1 V

J106 Pin 4 –5 V

J106 Pin 5 –15 V

Troubleshooting


Figure 6–42: Attenuator/Acquisition Troubleshooting Procedure

Are pins 26,

27, and 29 of P1 (see Figure 6–43)

about 400 mV 1 kHz

square waves?

Yes

No

No

Yes

Use this procedure to isolate a problem between the

A04 Acquisition, A08 Jumper, andA05 Attenuator boards.

This procedure assumes that the oscilloscope isnot displaying or not triggering properly on one ormore channels. It also assumes that the power-up

diagnostic fails with FAIL++Acq, FAIL++Attn,FAIL++Cpu/Acq..., or FAIL++Acq/Attn messages.This procedure is for CH 1, but you can used it for

all four input channels by substituting theappropriate data from Table 6–14.

Is the powerok?

Perform the Acquisition andAttenuator Power troubleshooting

procedure.

Perform the Low Voltage PowerSupply troubleshooting

procedure.

Attach a X10 probe to the CH 1 input.Attach the probe tip to the PROBE ADJUSTconnector on the front panel. Set the triggersource to CH1, and press AUTOSET. Set

the Vertical SCALE to 10 mV.

Set your bench oscilloscope to500 �s per division, 200 mV per

division, bandwidth limit to 20 MHz,and AUTO trigger.

The tested channel of the A05 Attenuator

board is ok.

Repeat this procedure foreach input channel.Using the A08 Jumper Board Assembly,

D1 Bus, and Board Supports removalprocedure (see page 6–43), remove the

A08 Jumper board.

Perform the I2Ctroubleshooting

procedure.

Are the signalsnot visible at

all?

Before removing the

A08 Jumper board were the signals double the amplitude,

and are they still double the

amplitude?

Replace the A04 Acquisition boardor the A08 Jumper board.

Yes

No

Yes

No

Are the CH1 Trigger, CH1

Vertical, and CH1 Vertical invertedsignals on J102 pins 26, 27, and 28of the A05 Attenuator board about

100 mV 1 kHz square waves?

Yes

No

Replace the A04 Acquisitionboard or the A08 Jumper

board.

Replace theA05 Attenuator board.

Perform the I2Ctroubleshooting

procedure.

Troubleshooting


CH2SIGP

CH2SIGN

CH1SIGPCH1SIGN (J102 on A05 Attenuator)

Vertical Signals

J101Pin 1

A05 Attenuator Board

A08 Jumper Board

CH1TRIG

CH2TRIG

CH3TRIG

CH4TRIG(Pin 2)

CH3SIGNCH3SIGP

CH4SIGN

CH4SIGPP1 Pin 1

TriggerSignals

Figure 6–43: A08 Jumper and A05 Attenuator Boards Signal Locations

Table 6–14: Channel and P1 Signal Locations

Channel NumberTrigger P1 Pin Number

Vertical P1 Pin Number

Vertical Inverted P1 Pin Number

1 26 27 29

2 18 19 21

3 10 11 13

4 2 3 5

Troubleshooting


No

Yes



Use this procedure to check thepower to the A04 Acquisition and

A05 Attenuator boards.

Using Table 6–16 and

Figure 6–45, are theA04 Acquisition boardpower supply voltages

ok?



Using Table 6–15 and

Figure 6–43, are theA05 Attenuator board power

supply voltages

ok?

Power to the A04 Acquisition andA05 Attenuator boards is ok.

No

Yes

Figure 6–44: Acquisition and Attenuator Power Troubleshooting Procedure

Table 6–15: A05 Attenuator Board Power

J101 Pin Voltage High Low

7 +5.1 V +5.15 V +4.9 V

10 +6 V +6.6 V +6.0 V

14 –6.4 V –6.0 V –6.5 V

16 +15 V +15.3 V +14.7 V

17 –15 V –14.7 V –15.3 V

Troubleshooting


Table 6–16: A04 Acquisition Board Power

J7 Voltage High Low

9 –15 V –14.7 V –15.3 V

12 –6.4 V –6.0 V –6.6 V

16 +5 V +5.15 V +4.9 V

19 +15 V +15.3 V +14.7 V

J7Pin 1

A04 Acquisition Board

Figure 6–45: A04 Acquisition Board Power Connector

Troubleshooting


Figure 6–46: Backplane Troubleshooting Procedure

Replace theA01 Backplane

module.

Perform the A25 LowVoltage Power Supply


Yes

No

Yes

No

No

Yes

Use this procedure totroubleshoot the A01 Backplane

board.

Press the ON/STBYbutton.

Does theoscilloscopepower up?

Does theoscilloscope power

up?

Disconnect P2 (between theA07 Auxiliary Power and A25 LowVoltage Power Supply modules).

Press the ON/STBY button.

Replace the A25 LowVoltage Power Supply

board.

Reconnect P2. Pressthe ON/STBY button.


up?

Yes

No

Replace either the A06 Front Panel,A01 Backplane, or A07 Auxiliary

Power boards.

Are the voltages at U1–U4 ok(see Table 6–17 and

Figure 6–47)?


module.

Are the voltages at J7

ok (see Table 6–18 andFigure 6–47)?

No

Yes

There is not a problemwith the

A01 Backplane.

Are the voltages at J8 ok(see Table 6–19)?

Does one of the

plug-in boards notwork, but the other

boards do?

Does the bad board

work in anotherA01 Backplane slot?

Replace the A01 Backplanemodule.

Replace the badboard.

Are thereintermittentproblems?

Replace the A01 Backplanemodule.

Are there still

problems?


module.

Yes

No

Yes

No

No

YesNo

Yes

No

Yes

Troubleshooting


Table 6–17: Regulator Voltages

Regulator Nominal Voltage Minimum Voltage Maximum Voltage

U1 pin 3 –12 V –11.5 V –12.5 V

U2 pin 3 +12 V +11.5 V +12.5 V

U3 pin 2 +6.3 V +5.07 V +6.57 V

U4 pin 3 –5 V –4.8 V –5.2 V

Table 6–18: J7 Voltages

Pin Nominal Voltage Minimum Voltage Maximum Voltage

1 –15 V –14.85 V –15.15 V

2 –15 V –14.85 V –15.15 V

7 –6.4 V –6.336 V –6.464 V

8 +15 V +14.85 V +15.15 V

9 +15 V +14.85 V +15.15 V

18 +5.1 V +5.151 V +5.05 V

19 +5.1 V +5.151 V +5.05 V

Table 6–19: J8 Front Panel Voltages

Pin Nominal Voltage Minimum Voltage Maximum Voltage

1 +15 V +14.25 V +15.75 V

2 +5 V +5.05 V +5.15 V

4 –5 V –5.05 V –5.2 V

5 –15 V –14.85 V –15.15 V

Troubleshooting


J7Pin 1

J8Pin 1

J6Pin 1

W2Pin 1

W1Pin 1

Figure 6–47: A01 Backplane Module

Troubleshooting


Figure 6–48: I2C Isolation Troubleshooting Procedure

Power off the oscilloscope andreplace the A03 CPU board.Power on the oscilloscope.

The A01 Backplane wasbad.

Power off the oscilloscope. Disconnect thecable to connector J101 on the

A05 Attenuator board. Power on theoscilloscope.

No

Yes

Repeat the procedure or contact your localTektronix service center.

Use this procedure toisolate problems on the

I2C bus.

Power off the oscilloscope. Using the Front Cover, Rear Cover, Cabinet, RearEMI Gasket, and Cabinet Handle and Feet

disassembly procedure, remove the cabinet.

Using the Console Port Set Up procedure,connect the console-port cable to the

oscilloscope and to your personal computer.


up normally?

Replace J101, theAttenuator/Backplane cable, or

the A05 Attenuator module.


up normally?

Power off the oscilloscope. Reconnect thecable to connector J101 on the

A05 Attenuator board. Remove theconnector to J7 on the A05 Attenuator

board. Power up the oscilloscope.

Replace J7, theAcquisition/Backplane cable,

or the A04 Acquisitionmodule?


up normally?

Power off the oscilloscope. Replacethe A01 Backplane module. Power

on the scope.

Yes

No

No

Yes

The A03 CPU board wasbad.


up normally?

No

Yes

Troubleshooting


Figure 6–49: Console Troubleshooting Procedure

Until changing a module fixes theproblem, replace in order the

A02 Display, the D1 Bus cable, theA09 DSP, and the A03 CPU modules.

Done.

No

Yes

Until changing a module fixes the problem,replace in order the A03 CPU, theA09 DSP, the A02 Display, and the

A01 Backplane modules.

Use this procedure whentroubleshooting with the

console.

Power off the oscilloscope. Using the Front Cover,Rear Cover, Cabinet, Rear EMI Gasket, and Cabinet

Handle and Feet disassembly procedure, remove the cabinet.

Using the Console Port Set Up procedure,connect the console-port cable to J3 on the

A03 CPU module.

Observe your terminal as you turn on the powerto the oscilloscope. Note the first failure or

where the tests stop.

Is the last displayed

message Acq Numberof Digitizers?

Perform the I2C Isolationtroubleshooting procedure.

Are the first characters ofthe name of the

first faileddiagnostic

dsp?

Until changing a module fixes theproblem, replace in order theA09 DSP, the A03 CPU, the

A02 Display, and the A01 Backplanemodules.

No

Yes

Are the first characters ofthe name of the

first faileddiagnostic

dsy?

No

Yes

No

Yes

Until changing a module fixes the problem,replace in order the A03 CPU, the A09 DSP,

the A02 Display, and the A01 Backplane modules.

Are the firstcharacters of thename of the firstfailed diagnostic

cpu?

No

Yes

Are the first characters of thename of the first failed

diagnostic atBus?


Options and Accessories

This chapter describes the various options and accessories that are available forthe TDS 420A, TDS 430A, and TDS 460A Digitizing Oscilloscopes.

OptionsThe following options are available.

See Option XL.

This option provides a video trigger. It lets you trigger on positive or negativesync pulses. It also lets you select interlaced field one, interlaced field two, orboth fields noninterlaced. You can define the signal class to be NTSC, PAL,SECAM, or you can customize the class.

See Option XL.

See Option XL.

With this option, Tektronix ships the digitizing oscilloscope configured forinstallation in a 19 inch wide instrument rack.

See Option XL.

With this option, Tektronix ships a front cover and pouch, RS-232 and aCentronics interface that can be used to obtain hardcopies of the oscilloscopescreen, a 120,000 Point Record Length, and advanced DSP math (the oscillo-scope can compute and display three advanced math waveforms: integral of awaveform, differential of a waveform, and an FFT (Fast Fourier Transform) of awaveform).

With this option, Tektronix ships a test data report for the oscilloscope.

Option 02: Front Coverand Pouch (TDS 400A

Only)

Option 05: Video Trigger

Option 13:RS-232/CentronicsHardcopy Interface

Option 1M: 120,000 PointRecord Length

Option 1R: RackmountedDigitizing Oscilloscope

Option 2F: Advanced DSPMath

Option XL: Options 02, 13,1M, and 2F

Option 95: Test DataReport



Besides the standard North American, 110 V, 60 Hz power cord, Tektronix shipsany of five alternate power cord configurations (listed in Table 7–1) with theoscilloscope when ordered by the customer.

Table 7–1: International Power Cords

Option Power Cord

A1 Universal European — 220 V, 50 Hz

A2 UK — 240 V, 50 Hz

A3 Australian — 240 V, 50 Hz

A4 North American — 240 V, 60 Hz

A5 Switzerland — 220 V, 50 Hz

With this option, Tektronix ships a French language user manual.

With this option, Tektronix ships a German language user manual.

With this option, Tektronix ships a Japanese language user manual.

Standard AccessoriesTable 7–2 lists the standard accessories that are included with the digitizingoscilloscope:

Table 7–2: Standard Accessories

Accessory Part Number

User Manual 070-9701-XX

Reference 020-2192-XX

Performance Verification 070-9705-XX

U.S. Power Cord 161-0230-01

Probes (one P6138/P6138A 10X Passive (TDS 420A)per channel) P6138A 10X Passive (TDS 430A)

P6138A 10X Passive (TDS 460A)

P6138A (single unit)

Options A1–A5:International Power Cords

Option L1: French UserManual

Option L3: German UserManual

Option L5: Japanese UserManual



Optional Accessories You can also order the optional accessories listed in Table 7–3:

Table 7–3: Optional Accessories

Accessory Part Number

Front Cover 200-3232-00

Service Manual 070-9703-XX

Printed Programmer Manual 070-9876-XX

Video Clamp 013-0278-00

Current Probe/Calibrator TCP202

High Voltage Differential Probe P5205

High Voltage Differential Probe P5200

Analog Differential Amplifier ADA400A

Plotter (GPIB and Centronics Standard) HC100

Plotter (Centronics Standard) HC200

Oscilloscope Cart K212

Oscilloscope Camera C9

Oscilloscope Camera Adapter 016-1154-00

Soft-Sided Carrying Case 016-1158-01

Transit Case 016-1157-00

GPIB Cable (1 meter) 012-0991-01

GPIB Cable (2 meter) 012-0991-00

Printer Pack with Seiko DPU-411 printer and accessory pouch TDS4F5P

Pouch (includes mounting plate) 016-1159-00

VGA Cable (Required to meet all emissions specifications) CTL3VGAMM-5 (LCOM part number)

Table 7–4 lists compatible probes recommended for use with your digitizingoscilloscope:

Table 7–4: Compatible Probes

Probe Type Tektronix Model Description

Passive, high impedance voltage P6138A P6101B

10X, 400 MHz1X, 15 MHz

Passive, SMD P6563A 20X, 500 MHz

Accessory Probes



Table 7–4: Compatible Probes (Cont.)

Probe Type DescriptionTektronix Model

Passive, low impedance Zo P6156 10X, 3.5 GHz, for 50 � inputs (1X, 20X, 100X optional)

Passive, high voltage P5100P6015A

100X, 2.5 kV, DC + peak AC1000X, 20 kV, DC + peak AC

Active, high speed voltage P6243P6204

DC to 1 GHz FET, TekProbe poweredDC to 1 GHz FET, DC Offset capability (requires Tektronix 1103TekProbe Power Supply for offset capability)

Active, differential voltage P6046P5205

1X/10X, 250 V, DC to 100 MHz50X/500X, 1300 V, DC to 100 MHz

Current AM 503SAM 503S Opt. 03AM 503S Opt. 05TCP202P6021P6022CT-1/CT-2

CT-4

AC/DC, Uses DC to 50 MHz A6302 Current ProbeAC/DC, Uses DC to 15 MHz A6303 Current ProbeAC/DC, Uses DC to 100 MHz A6312 Current ProbeAC/DC, DC to 50 MHz, TekProbe poweredAC, 120 Hz to 60 MHzAC, 935 kHz to 120 MHzDesigned for permanent or semi-permanent in-circuit installationCT-1: 25 kHz to 1 GHz, 50 � inputCT-2: 1.2 kHz to 200 MHz, 50 � input

Current Transformer for use with AM 503S and P6021. Peak pulse1 kA, 0.5 Hz to 20 MHz with AM 503S

Logic Word Trigger P6408 16 channel, one qualifier channel, TTL compatible, +5 V powersupply required

Optical (Opto-Electric Converters) P6701AP6703AP6711P6713

500 to 950 nm, DC to 850 MHz, 1 V/mW1100 to 1700 nm, DC to 1 GHz, 1 V/mW500 to 950 nm, DC to 250 MHz, 5 V/mW1100 to 1700 nm, DC to 300 MHz, 5 V/mW



Table 7–5 lists optional accessories that are Tektronix software productsrecommended for use with your digitizing oscilloscope:

Table 7–5: Accessory Software

Software Part Number

Wavewriter: AWG and waveform creation S3FT400

LabWindows for DOSfor CVI

LWDOSLWCVI

WaveStar WSTR31

The warranty statement for this product is after the title page of this manual.

Tektronix offers the following services that you can purchase any time during thewarranty period of this product:

� REP (Repair) Service Assurance provides one year of post-warranty repairsupport. It is available in one year increments up to two years.

� CAL (Calibrate) Service Assurance provides one year of calibration support.It is available in one year increments up to five years.

For further information contact your Tektronix Representative.

Accessory Software

Warranty Information

Service Assurance




Electrical Parts List

The modules that make up this instrument are often a combination of mechanicaland electrical subparts. Therefore, all replaceable modules are listed in Chap-ter 10, Mechanical Parts List. Refer to that chapter for part numbers when usingthis manual.

Electrical Parts List



Diagrams

This chapter contains the block diagram and the interconnection diagram for thisoscilloscope. If servicing a TDS 430A, ignore all references to CH 3 and CH 4.

SymbolsGraphic symbols and class designation letters are based on ANSI StandardY32.2–1975. Abbreviations are based on ANSI Y1.1–1972.

Logic symbology is based on ANSI/IEEE Std 91–1984 in terms of positivelogic. Logic symbols depict the logic function performed and can differ from themanufacturer’s data.

A tilde (~) preceding a signal name or an asterisk following a signal nameindicates that the signal performs its intended function when in the low state.

Other Tektronix, ANSI, and military standards are also used in the preparation ofdiagrams by Tektronix, Inc.

Diagrams


Figure 9–1: TDS 400A Interconnections

J103

CAL SIGJ405

J101

10 PINS

4 PINS

A17 BEZEL BUTTON

10 PINSMENUSWITCHES

*

P1

A16 FLEX

14 PINS

*

P1

A05 ATTENUATOR

A06 FRONT PANEL

J104 J106

10 PINS

5 PINS14 PINS

10

5

#

#

A1W1

18

A1W2

#

J101

J102

18 PINS

34 PINS

9CH 1

CH 3

CH 4

CH 2

J10

J20

J30

J40

P5

P4

P3

P2

J4

A08 JUMPER

J7J9

P1

P2

34 PINS

34 PINS20 PINS

J6

*

A2520

LOW VOLTAGE PWR SUPPLY

#

J222 PINS

REM

W3W5

J15 PINS

3 PINS

50

1 3

2

A7W5

A7W2

A04 ACQUISITION

J5

J8

50 PINS

OPTION14 PINS

2 PINSINTRG(BACK PANEL)

* NO BLOCK DIAGRAMS

# THESE REPLACEABLE CABLESFOR THESE BOARDS.

ARE LISTED IN SECTION 10.

FAN

LINE FILTER

B15

AUXILIARY POWERA07

J3P3

W4

2 PINS2

10 PINSJ7

J42 PINS

AUX TRIG/EXT CLOCK<6V 34 PINS

PWR

(TDS 420A & TDS 460A

ONLY)

*

Diagrams


Figure 9–1: TDS 400A Interconnections (Cont.)

CPU

J6

J5

GPIB

3.0V2 PINS

25 PINSIEEE STD

TO BT10

488 PORT

A03

J3

J1

J2

RS–232

DIAG PORT 10 PINS

10 PINS

100 PINSFROMSYS50

J410

PINS

W1

J8

P1 & P2 J3

J2

5 PINS

98 PINS

98 PINS

18 TERMINATIONS

98 PINS

DTE PORTRS–232

P1 & P398 PINS

9 PINSJ60

2 PINJ1

9

7V,2A

A09 DSP

W2

P1 & P2 J5

J198 PINS

20 TERMINATIONS

98 PINS98 PINS

3.0V

J150 PINS

2 PINS

50

TO BT12

J1

J7

8 PINSJ2

8

50

15 PINSVIDEOVGA

OUTPUTJ4P1 & P2

98 PINS98 PINS A10 SERPAR

25 PINSJ50

25 CENTRONICSCOMPATIBLE

DISPLAY

J722 PINS22

A02

#

A26 MONITOR

J90110 PINS2

#

# A01 BACKPLANE

J610 PINS10

FUSED

50 PINS

FLOPPYDRIVE

P38 26

Diagrams


Figure 9–2: TDS 400A Block Diagram

A05 ATTENUATOR

A08JUMPER

CH 1

CH 2

CH 3

CH 4

A04 ACQUISITION

LINE FILTER

A07

AUX POWER

A25

ATTENUATORS

PREAMPS

ACQUISITIONSYSTEM

A01 BACKPLANE

FAN

FUSE

POWERSWITCH LOW VOLTAGE POWER SUPPLY

A09DSP

BATTERY

50

22

10

2

2

1

2

FL52

1

PROBE ADJ

GND

10MENU SWITCHES

A17 BEZEL BUTTON

14PROBE CODINGINTERFACE

A15

5A06 FRONT PANEL

10

34 34

20

2

98

50

FRONT PANELSWITCHES

FRONT PANELPOTS

FRONT PANELLEDS

PROBECOMPENSATION

2

3

1

1

(TDS 420A & TDS 460A ONLY)

(TDS 420A & TDS 460A ONLY)

Diagrams


Figure 9–2: TDS 400A Block Diagram (Cont.)

AUX TRIGGER/EXT CLOCK � 6V

REAR PANEL

2

BATTERY

A03 CPU

DIAG PORT

RS-232 PORT

10

10

25

15

8

VIDEOVGA

A26 MONITOR

MONITOR ASSEMBLY

DISPLAY

VIDEOA02

2

98

50

1

GPIBIEEE 488

PORT

PROCESSORSYSTEM

98

OPTION 13

A10 SERPAR

7V, 2A FUSED

RS-232 DTE PORT

2

9

25 CENTRONICSCOMPATIBLE

FloppyDrive 26

Diagrams



Replaceable Parts

This section contains a list of the replaceable modules for the <instrument>. Usethis list to identify and order replacement parts.

Parts Ordering InformationReplacement parts are available through your local Tektronix field office orrepresentative.

Changes to Tektronix products are sometimes made to accommodate improvedcomponents as they become available and to give you the benefit of the latestimprovements. Therefore, when ordering parts, it is important to include thefollowing information in your order:

� Part number (see Part Number Revision Level below)

� Instrument type or model number

� Instrument serial number

� Instrument modification number, if applicable

If you order a part that has been replaced with a different or improved part, yourlocal Tektronix field office or representative will contact you concerning anychange in part number.

Change information, if any, is located at the rear of this manual.

Tektronix part numbers contain two digits that show the revision level of thepart. For most parts in this manual, you will find the letters XX in place of therevision level number.

670-7918-03

Part Number Revision Level

670-7918-XX

Revision Level May Show as XX

When you order parts, Tektronix will provide you with the most current part foryour product type, serial number, and modification (if applicable). At the time ofyour order, Tektronix will determine the part number revision level needed foryour product, based on the information you provide.

Part Number RevisionLevel

Replaceable Parts


Modules can be serviced by selecting one of the following three options. Contactyour local Tektronix service center or representative for repair assistance.

Module Exchange. In some cases you may exchange your module for a reman-ufactured module. These modules cost significantly less than new modules andmeet the same factory specifications. For more information about the moduleexchange program, call 1-800-TEK-WIDE, extension 6630.

Module Repair and Return. You may ship your module to us for repair, after whichwe will return it to you.

New Modules. You may purchase replacement modules in the same way as otherreplacement parts.

Using the Replaceable Parts ListThis section contains a list of the mechanical and/or electrical components thatare replaceable for the <instrument>. Use this list to identify and order replace-ment parts. The following table describes each column in the parts list.

Parts List Column Descriptions

Column Column Name Description

1 Figure & Index Number Items in this section are referenced by figure and index numbers to the exploded viewillustrations that follow.

2 Tektronix Part Number Use this part number when ordering replacement parts from Tektronix.

3 and 4 Serial Number Column three indicates the serial number at which the part was first effective. Column fourindicates the serial number at which the part was discontinued. No entries indicates the part isgood for all serial numbers.

5 Qty This indicates the quantity of parts used.

6 Name & Description An item name is separated from the description by a colon (:). Because of space limitations, anitem name may sometimes appear as incomplete. Use the U.S. Federal Catalog handbookH6-1 for further item name identification.

7 Mfr. Code This indicates the code of the actual manufacturer of the part.

8 Mfr. Part Number This indicates the actual manufacturer’s or vendor’s part number.

Abbreviations conform to American National Standard ANSI Y1.1–1972.

The table titled Manufacturers Cross Index shows codes, names, and addressesof manufacturers or vendors of components listed in the parts list.

Module Servicing

Abbreviations

Mfr. Code to ManufacturerCross Index


CROSS INDEX – MFR. CODE NUMBER TO MANUFACTURER

Mfr.Code Manufacturer Address City, State, Zip Code

S3109 FELLER 72 VERONICA AVE UNIT 4 SUMMERSET NJ 08873

S3629 SCHURTER AG HC/O PANEL COMPONENTS CORP

2015 SECOND STREET BERKELEY CA 94170

S4246 JAPAN SERVO CO LTD 7 KANDAMITOSHIRO–CHO CHIYODA–KU

TOKYO JAPAN

TK0435 LEWIS SCREW CO 4300 S RACINE AVE CHICAGO IL 60609–3320

TK0860 LABEL GRAPHICS 6700 SW BRADBURY CT PORTLAND OR 97224

TK1163 POLYCAST INC 9898 SW TIGARD ST TIGARD OR 97223

TK1891 PRESTOLE CORP 34589 GLENDALE ST LIVONIA MI 48150–1303

TK1908 PLASTIC MOLDED PRODUCTS 4336 SO ADAMS TACOMA WA 98409

TK1918 SHIN–ETSU POLYMER AMERICA INC 1181 NORTH 4TH ST SAN JOSE CA 95112

TK1935 ACCRA–FAB INC 11007 NE 37TH CIRCLE VANCOUVER WA 98682

TK2058 TDK CORPORATION OF AMERICA 2055 GATEWAY PLACESUITE 200

SAN JOSE CA 95110

TK2432 UNION ELECTRIC 15/F #1, FU–SHING N. ROAD

TAIPEI, TAIWAN ROC

TK2469 UNITREK CORPORATION 3000 LEWIS & CLARK WAYSUITE #2

VANCOUVER WA 98601

TK2478 GRIMES COMPANY 115 S AROVISTA CIRCLE BREA CA 92631

0DWW6 MICRO POWER ELECTRONICS 7973 SW CIRRUS DRIVEBLDG. #22

BEAVERTON OR 97005

0JR05 TRIQUEST CORP 3000 LEWIS AND CLARK HWY

VANCOUVER WA 98661–2999

0KB01 STAUFFER SUPPLY 810 SE SHERMAN PORTLAND OR 97214

00779 AMP INC 2800 FULLING MILLPO BOX 3608

HARRISBURG PA 17105

07416 NELSON NAME PLATE CO 3191 CASITAS LOS ANGELES CA 90039–2410

1JJ96 KAM ELECTRIC CO 11866 SLATER AVE NE KIRKLAND WA 98034

18565 CHOMERICS INC 77 DRAGON COURT WOBURN MA 01801–1039

2K262 BOYD CORP 6136 NE 87TH AVEPO BOX 20038

PORTLAND OR 97220

22670 G M NAMEPLATE INC 2040 15TH AVE WEST SEATTLE WA 98119–2728

24931 SPECIALTY CONNECTOR CO INC 2100 EARLYWOOD DRPO BOX 547

FRANKLIN IN 46131

30817 INSTRUMENT SPECIALTIES CO INC EXIT 53 RT 80BOX A

DELAWARE WATER GAP PA 18327

34416 PARSONS MFG CORP 1055 OBRIAN DR MENLO PARK CA 94025–1408

50356 TEAC AMERICA INC 7733 TELEGRAPH RDPO BOX 750

MONTEBELLO, CA 90640–6537

50463 POWER SYSTEMS INC. 45 GRIFIN ROAD SOUTH LINFIELD, CT 06002


CROSS INDEX – MFR. CODE NUMBER TO MANUFACTURER

Mfr.Code City, State, Zip CodeAddressManufacturer

61857 SAN–0 INDUSTRIAL CORP 85 ORVILLE DRPO BOX 511

BOHEMIA LONG ISLAND NY 11716–2501

70903 COOPER BELDEN ELECTRONICS WIRE AND CABLESUB OF COOPER INDUSTRIES INC

80009 TEKTRONIX INC 14150 SW KARL BRAUN DRPO BOX 500

BEAVERTON OR 97077–0001


Fig. &Index No.

TektronixPart No.

Serial No. Effective Dscont

Qty

Name & Description

Mfr.Code

Mfr. Part No.

10–1–1 390–1109–02 1 CABINET,SCOPE:ALUMINUM,TEK BLUE 80009 390110902

–2 367–0356–01 1 HANDLE,CARRYING 80009 367035601

–3 212–0144–00 2 SCREW,TPG,TF:8–16 X 0.562 L,PLASTITE 0KB01 ORDER BY DESC

–4 348–0659–00 2 FOOT,CABINET:BLACK POLYURETHANE 0JR05 ORDER BY DESC

–5 348–0764–03 1 SHLD GSKT,ELEK:0.125 X 0.188,WIRE MESH,37 L 18565 ORDER BY DESC

–6 334–8176–00 1 MARKER,IDENT:MKD REAR 07416 ORDER BY DESC

–7 334–8561–00 1 MARKER,IDENT:OPTIONS 80009 334856100

–8 161–0230–01 1 CABLE ASSY,PWR,:3,18 AWG,92 L,SVT,TAN(STANDARD ACCESSORY)

TK2432 ORDER BY DESC

–9 343–1213–00 1 CLAMP,PWR CORD:POLYMIDE(STANDARD ACCESSORY)


–10 200–2264–00

200–2265–00

1

1

CAP,FUSEHOLDER:3AG FUSES(AMERICAN)CAP,FUSEHOLDER:5 X 20MM FUSES(EUROPEAN)

S3629

S3629

FEK 031 1666

FEK 031.1663

–11 159–0014–00

159–0255–00

1

1

FUSE,CARTRIDGE:3AG,5A,250V,0.8SEC(AMERICAN)FUSE,CARTRIDGE:FAST BLOW,4A,125V(EUROPEAN)

61857

61857

SS2–5A

EQ4A

–12 211–0691–00 4 SCREW,MACHINE:6–32 X 0.625,PNH,STL 0KB01 ORDER BY DESC

–13 200–3991–01 1 COVER,REAR:HARD,POLYCARBONATE,LEXAN 80009 200399101

–14 211–0730–00 1 SCR,ASSEM WSHR:6–32 X 0.375,PNH,STL CD PL 0KB01 ORDER BY DESC

–15 211–0840–00 1 SCREW,MACHINE:M2.6 X 0.45MM PITCH X 4.0 MM 0KB01 .26C4MXP

–16 259–0085–00 1 FLEX CIRCUIT:PROBE CODE 80009 259008500

–17 348–1258–00 4 SHLD,GASKET,ELE:2 LAYER,0.094 X 0.188 X 8.750 80009 348125800

–18 672–1470–00

672–1436–00

672–1437–00

1

1

1

CIRCUIT BD ASSY:FRONT PANEL ASSY(TDS430A ONLY)CIRCUIT BD ASSY:FRONT PANEL ASSY(TDS420A ONLY)CIRCUIT BD ASSY:FRONT PANEL ASSY(TDS460A ONLY)

80009

80009

80009

672147000

672143600

672143700

–19 384–1689–01 6 SHAFT EXTENDER:ACETAL 80009 384168901

–20 366–2113–00 3 KNOB:MEDIUM,DETENTED TK1163 ORDER BY DESC

–21 366–2111–00 3 KNOB:SMALL,FLUTED TK1163 ORDER BY DESC

–22 200–3232–01 1 COVER,FRONT:ASB(OPTIONAL ACCESSORY)


–23 354–0709–00

354–0736–00

1

1

RING,TRIM:LEXAN 940(TDS420A/460A ONLY)TRIM,DECORATIVE:FRONT(TDS430A ONLY)

80009

80009

354070900

354073600

–24 366–2164–00 14 PUSH BUTTON:SMOKE TAN 80009 366216400

–25 334–8820–00

334–8821–00

334–9232–00

1

1

1

MARKER,IDENT:BEZEL(TDS460A ONLY)MARKER,IDENT:BEZEL(TDS420A ONLY)MARKER,IDENT:BEZEL(TDS430A ONLY)

80009

80009

80009

334882000

334882100

334923200


Fig. &Index No.

Mfr. Part No.

Mfr.Code

Name & Description

Qty


TektronixPart No.

10–1–26 119–5677–01 1 DISK DRIVE:FLOPPY,3.5 INCH,1.44MB 50356 FD–04HF–2300

–27 200–4219–00 1 COVER:DISK DRIVE,3.5 INCH 80009 200421900

–28 131–5965–00 2 CONTACT,ELEC:ESD PROTECTION,0.005 ST STL 80009 131596500

–29 260–2539–00 1 SWITCH SET:BEZEL TK1918 260253900

–30 259–0086–00 1 FLEX CIRCUIT:BEZEL BUTTON 07416 ORDER BY DESC

–31 105–1081–00211–0866–01

11

BRKT,ADAPTER:FLOPPY DISK DRIVESCREW,PHIL, M2.5 x 10, PNH, BRZN

TK11630KB01

105108100211–0866–01


1

23

4

5

67 8

910

11

12

13

14

15

1617

18

1920

21

2223

2425

2627

28

29

30

31

Figure 10–1: External and Front Panel Modules


Fig. &Index No.

TektronixPart No.

Serial No.Effective Dscont

Qty

Name & Description

Mfr.Code

Mfr. Part No.

10–2–1 426–2436–01 1 FRAME,CRT FLTR:POLYCARBONATE TK1163 ORDER BY DESC

–2 348–1291–00 2 SHLD,GSKT ELEK:CLIP–ON EM GASKET 30817 9760–5090–20

–3 213–0882–00 37 SCREW,TPG,TR:6–32 X 0.437 TAPTITE,PNH,STL 0KB01 ORDER BY DESC

–4 640–0079–02 1 DISPLAY MODULE:7 INCH, MONOCHROME P31 80009 640007902

–5 426–2426–00 1 FRAME,FAN MTG:POLYCARBONATE 80009 426242600

–6 671–1682–00 1 CIRCUIT BD ASSY:AUXILIARY POWER 80009 671168200

–7 119–1770–00 1 FAN ASSEMBLY:12VDC,1.72W,35CFM W/CONN S4246 CUDC12D4

–8 119–3939–02 1 POWER SUPPLY:100VAC AT 440 HZ 50463 PSI–135X–38 69

–9 386–6159–00 1 SUPPORT,CKT BD:BACK PLANE & PWR SPLY 80009 386615900

–10 334–3003–00 1 MARKER,IDENT:DANGER POWER LINE TK0860 ORDER BY DESC

–11 119–5028–00 1 FILTER,RFI:4A,250V,48 TO 440HZ 80009 119502800

–12 131–0955–00 1 CONN,RF JACK:BNC,50 OHM,FEMALE,STR 00779 87–3334–017

–13 407–4032–00 2 BRACKET,CKT BD: 80009 407403200

–14 211–0722–00 4 SCREW,MACHINE:6–32 X 0.25,PNH,STL 0KB01 ORDER BY DESC

–15 671–3268–01 1 CIRCUIT BD ASSY:CPU 80009 671326801

–16 671–3902–00 1 CIRCUIT BD ASSY:DISPLAY 80009 671390200

–17 671–3588–00

671–3284–00

1

1

CIRCUIT BD ASSY:DSP(STANDARD)CIRCUIT BD ASSY:DSP(OPTION 1M)

80009

80009

671358800

671328400

–18 386–6158–00 3 SUPPORT,CKT BD:MAT MATERIAL 80009 386615800

–19 146–0056–02 2 BATTERY:3V,1200MAH,2/3A LITHIUM BATTERY 0DWW6 ORDER BY DESC

–20 671–3597–01

671–1685–12

671–3980–00

1

1

1

CIRCUIT BD ASSY:ACQUISITION(TDS420A ONLY)CIRCUIT BD ASSY:ACQUISITION(TDS460A ONLY)CIRCUIT BD ASSY:ACQUISITION(TDS430A ONLY)

80009

80009

80009

671359701

671168512

671398000

–21 344–0116–00 2 RTNR,CAPACITOR:0.625 DIA,STEEL TK1891 E50003–007

–22 671–1683–00 1 CIRCUIT BD ASSY:JUMPER 80009 671168300

–23 671–3595–01

671–1686–07

671–3979–00

1

1

1

CIRCUIT BD ASSY:ATTENUATOR(TDS420A ONLY)CIRCUIT BD ASSY:ATTENUATOR(TDS460A ONLY)CIRCUIT BD ASSY:ATTENUATOR(TDS430A ONLY)

80009

80009

80009

671359501

671168607

671397900

–24 337–3713–01 1 SHIELD,ELEC:ATTENUATOR TK1935 337371301

–25 671–1676–03 1 CIRCUIT BD ASSY:BACKPLANE 80009 671167605

–26 200–3660–00 1 COVER,AUTO CAL:POLYCARBONATE TK1163 ORDER BY DESC

–27 441–2072–00 1 CHASSIS ASSY:ALUMINUM 80009 441207200


A4

A8A5

A3

A7

A1

A2

A9

12

3

45 6

78

9

10

11

1213

14

15

16

17

1819

3

3

3

3

14

14

14

3

20

21

2223

24

25

26

27

Figure 10–2: Internal Modules


Fig. &Index No.

TektronixPart No.


Qty

Name & Description

Mfr.Code

Mfr. Part No.

10–3–1 174–2661–00 1 CABLE,SP,ELEC:18 AWG,AMP TK2469 174–2661–00

–2 174–2282–00 1 CA ASSY,SP,ELEC:FLAT FLEX,15.8L TK2469 174–2282–00

–3 276–0849–00 2 CORE,EM:EMI SUPPRESS,RBN CA,RECTANGLE 1JJ96 BFS 33.5X8X6.5 SLOT 27

–4 253–0176–00 1 TAPE,PRESS SENS:VINYL FOAM,0.5 X 0.062 2K262 ORDER BY DESC


–6 174–2373–00 1 CA ASSY,SP,ELEC:2,18 AWG,2.0 L TK2469 174–2373–00

–7 174–2288–00 1 CA ASSY,SP,ELEC:DESCETE,PSC,3.5L TK2469 174–2288–00

–8 210–0457–00 2 NUT,PL,ASSEM WA:6–32 X 0.312,STL CD PL TK0435 ORDER BY DESC

–9 174–2631–00 1 CABLE ASSY,PWR:1460 PVC,18 AWG TK2469 174–2631–00

–10 174–2281–01 1 CA ASSY,SP,ELEC:50,28 AWG,2.3 L,FLAT CABLE TK2469 ORDER BY DESC



–13 174–3135–00 1 CABLE ASSY,SP:FLAT,FLX,26,1MM,15.0L(DISK DRIVE)

80009 174313500

–14 174–2284–00 1 CA ASSY,SP,ELEC:FLAT FLEX,8.8L 80009 174228400


1

23

4

5

6

78

98

10

11

12

5

13

14

3

Figure 10–3: Cables and Routing


Fig. &Index No.

TektronixPart No.


Qty

Name & Description

Mfr.Code

Mfr. Part No.

STANDARD ACCESSORIES

–––––––– 1 ACCESSORY PKG:(2) P6138A 1.3M PROBES

070–9701–XX 1 MANUAL,TECH:TUTORIAL/USER,ENGLISH 80009 0709701XX

020–2192–XX 1 MANUAL,TECH:QUICK REF 80009 0202192XX

070–9703–XX 1 MANUAL,TECH:SERVICE 80009 0709703XX

070–9705–XX 1 MANUAL,TECH:PERFORMANCE VERIFICATION 80009 0709705XX

–––––––– 1 CABLE ASSY,PWR,:3,18 AWG,92 L,SVT,TAN(STANDARD–SEE FIGURE 10–1–8)


161–0104–05 1 CABLE ASSY,PWR,:3,18 AWG,240V,98.0 L(OPTION A3–AUSTRALIAN)

S3109 SAA/3–OD3CCFC3X

161–0104–06 1 CABLE ASSY,PWR,:3 X 0.75MM SQ,220V,98.0 L(OPTION A1–EUROPEAN)

S3109 VIIGSOPO–HO5VVF

161–0104–07 1 CABLE ASSY,PWR,:3,1.0MM SQ,240 VOLT,2.5 M(OPTION A2–UNITED KINGDOM)

S3109 ORDER BY DESC

161–0104–08 1 CABLE ASSY,PWR,:3,18 AWG,98 L,SVT,GREY/BLK(OPTION A4–NORTH AMERICAN)

70903 ORDER BY DESC

161–0167–00 1 CABLE ASSY,PWR,:3.0 X 0.75,6A,240V,2.5M L(OPTION A5–SWITZERLAND)

S3109 ORDER BY DESC

–––––––– 1 CLAMP,PWR CORD:POLYMIDE(SEE FIGURE 10–1–9)



Fig. &Index No.

Mfr. Part No.

Mfr.Code

Name & Description

Qty


TektronixPart No.

OPTIONAL ACCESSORIES

003–1463–00 1 WRENCH,BNC:WRENCH FOR BNC FIXTURE 80009 003146300

003–1464–00 1 FIXTURE,BNC:BNC FIXTURE FOR TDS400 80009 003146400

012–0991–00 1 CABLE,COMPOSITE:IDC,GPIB:2 METER,24 COND 00779 553577–3

012–0991–01 1 CABLE,GPIB:LOW EMI,1 METER 00779 553577–2

016–1154–00 1 HOOD ASSEMBLY:2KDSO 80009 016115400

016–1157–00 1 CASE,CARRYING:26 X 22 X 12,HARD TRANSFER 34416 ORDER BY DESC

016–1158–01 1 CASE,CARRYING:SOFT PADDED,OPTIONS 80009 016115801

016–1166–00 1 RACK MOUNT KIT:RACK MOUNT TDS400 80009 016116600

063–2634–00 1 SOFTWARE PKG:FIELD ADJUST 80009 063263400

067–0208–00 1 FIXTURE,CAL:RECOVERING TIME 80009 067020800

–––––––– 1 COVER,FRONT:ASB(SEE FIGURE 10–1–22)

070–8521–XX 1 MANUAL,TECH:RACKMOUNT(OPTION 1R ONLY)

80009 0708521XX

070–8567–XX 1 MANUAL,TECH:RS–232/CENTRONICS(OPTION 13 ONLY)

80009 0708567XX

070–8722–XX 1 MANUAL,TECH:INSTRUCTION(TDS4F5P ONLY)

80009 0708722XX

070–8762–XX 1 MANUAL,TECH:USER,VIDEO DISPLAY(OPTION 05 ONLY)

80009 0708762XX


Documents

TDS 420A, TDS 430A & TDS 460A Digitizing Oscilloscopes 070